ABSTRACT. Cheese whey (CW) is the primary effluent of the dairy industry and must be treated to prevent environmental issues. Hydrogen can be produced in the first stage of wastewater treatment. Research has explored the potential of cheese whey for hydrogen production in dark fermentation systems, primarily utilizing carbohydrates (lactose) found in the CW. However, lactic acid bacteria in the CW leads to natural fermentation, converting lactose into lactate. Hydrogen can be produced from lactate through the acrylate and the pyruvate-ferredoxin oxidoreductase pathways. Under such a pathway, microorganisms like Clostridium use lactate and acetate to produce butyrate and hydrogen. This study assessed and optimized the hydrogen production from lactate using fermented cheese whey (FCW) as a substrate, concentrating on the lactate-acetate pathway, and the microbial community was analyzed. The lactate pathway was analyzed, considering operating parameters such as hydraulic retention time (HRT) and pH. An expanded granular sludge bed reactor with a working volume of 2.2 L was used and operated for 90 days. Initially, the reactor was fed with CW, followed by FCW. Results showed that a hydrogen production rate (HPR) of 0.48 L H2/L·d was obtained when the reactor was supplied solely with FCW at an HRT of 6 hours. Reducing the HRT to 4.5 hours resulted in a 75% increase in HPR. A decrease in pH (from 6 to 5) led to a 1.5-fold increase in HPR (1.2 L H2/L·d). The effect of acetate addition was evaluated, yielding an HPR of 3.2 L H2/L·d through the lactate-acetate pathway and including iron (50 mg Fe/L), an enzyme cofactor, boosted productivity up to 6.73 L H2/L·d, among the highest productivity levels reported to date with real effluents. Microbial community analysis revealed interactions between lactic acid bacteria (Lactobacillus) and hydrogen producers (Caproiciproducens and Clostridium sensu stricto 12). This study evidenced the potential of the lactate-acetate pathway to improve hydrogen production rates from an agro-industrial effluent.

ABSTRACT. Dark fermentation is a light-independent anaerobic process carried out by bacteria, enabling biohydrogen production from organic waste through microbial metabolism, typically yielding byproducts such as organic acids and alcohols. However, these systems often exhibit instability, partly due to variability in microbial community dynamics. Optimizing the structure and balance of microbial populations is therefore essential to enhance biohydrogen yields. Among the microbial groups involved, lactic acid bacteria (LAB) are consistently detected in fermentative environments, and their presence has been associated to a dual influence on hydrogen yields. LAB can promote hydrogen yields through synergistic interactions with hydrogen-producing bacteria (HPB), such as cross-feeding; however, they may also reduce yields by competing for substrates or releasing inhibitory metabolites.

Despite this, the role of HPB/LAB ratios as a modulating factor in fermentative systems remains underexplored. This study assessed the impact of microbial ratios on hydrogen yields using complex substrates, such as agroindustrial effluents. Microbial community composition was characterized through 16S rRNA gene amplification and high-throughput sequencing using the Illumina MiSeq platform. Statistical analyses revealed that the effect of LAB:HPB ratios is substrate dependent. In the second stage, cheese whey was used as a model substrate to determine conditions under which specific ratios enhance hydrogen yields. Results showed that hydraulic retention time (HRT) between 10 and 18 hours did not significantly affect hydrogen production but did influence the HPB/LAB ratio. An HRT of 10 hours led to lower HPB presence; however, hydrogen production remained stable and reached a maximum of 2.6 L H2/L∙ d due to other contributing factors. This study proposes the HPB/LAB ratio as a potential operational parameter for process optimization. Further research is required to validate this variable across substrates and scales.

Acknowledgements This research was funded by the projects PAPIIT IN104825 DGAPA-UNAM, Mexico, and “Interdisciplinary Research Groups,” Institute of Engineering, UNAM.

ABSTRACT. Hydrogen production from organic waste through dark fermentation is one of the most environmentally viable methods, as it simultaneously generates energy and reduces the release of polluting waste into the environment. To improve the economic feasibility of this process, it is essential to optimize operating conditions to maximize not only hydrogen production but also the generation of organic acids, which can serve as substrates for further waste processing via anaerobic digestion or for the production of polyhydroxyalkanoates. Operational pH and initial substrate composition are the primary factors influencing the metabolic pathways toward desired products. Previous studies have shown that neutral and alkaline pH conditions favor the hydrolysis of complex molecules and enhance acid production yields. The aim of this study was to determine the influence of operational pH on hydrogen and metabolite production from tequila vinasse. Mesophilic fermentations were carried out in duplicate at controlled pH values of 6.0, 7.0, and 8.0, using a mixed microbial culture as inoculum. Results showed a hydrogen yield of 60 mL/gCOD at pH 6.0, mainly driven by microorganisms of the genera Clostridium, Lactobacillus, Enterobacter, and Klebsiella. At neutral and alkaline pH levels, hydrogen production was negligible, and ethanol became the main metabolite, with yields ranging from 8 to 13% of the added COD. An increased proliferation of Enterobacter and Klebsiella was observed under neutral and alkaline conditions, correlating with ethanol production. While previous studies typically report that ethanol production is favored at low pH (<5.0), the findings of this study, along with other reports, demonstrate that ethanol production can also be promoted at neutral and alkaline pH through the growth of Enterobacter and Klebsiella. These results reinforce that metabolic profiles are not fixed for each pH value and that pH-specific characterizations are necessary for each type of substrate. Overall, this study highlights that acidic conditions are optimal for hydrogen production with the growth of Lactobacillus and Clostridium. In contrast, neutral and alkaline pH values are unsuitable for hydrogen production and further effluent processing, as high ethanol production competes with organic acid formation. Future studies should focus on optimizing operating pH values below 6.0 to enhance hydrogen and metabolite yields.

ABSTRACT. Nixtamalization, the traditional cooking process of maize grains, generates large volumes of an alkaline, calcium-rich, yellow effluent known as nejayote. This wastewater is typically discarded without treatment, posing serious environmental risks, particularly in countries where maize-based products are dietary staples. However, nejayote holds untapped potential, it can be revalorized to produce gaseous biofuels like hydrogen, offering a sustainable and economically viable waste management strategy. This study aimed to assess the hydrogen production potential of chemically treated nejayote in a UASB (Upflow Anaerobic Sludge Blanket) reactor. Prior to digestion, the nejayote underwent chemical precipitation to remove calcium, improving its suitability as a substrate for anaerobic processes. The de-calcified nejayote was then physically and chemically characterized, and tested under three conditions: undiluted, and diluted with water in a 1:1 and 1:3 ratio. The highest hydrogen production, measured at 2 L/d, was observed when using undiluted nejayote. Additionally, methane, another valuable gaseous biofuel, was also produced in significant quantities of up to 450 mL/d. Organic load removal was evaluated via Chemical Oxygen Demand (COD), reaching reduction rates of 307 mg/L·h. The process also resulted in an increase of intermediate metabolites, which serve as indicators of system stability. To better understand the biological aspects of the process, microbial community analyses were conducted at each operational stage using 16S rRNA sequencing. These analyses revealed shifts in microbial populations, providing insights into the metabolic pathways contributing to hydrogen and methane production. The findings demonstrate that nejayote, commonly seen as a pollutant, can be transformed into a source of clean energy, supporting circular economy initiatives in agro-industrial contexts. This approach not only mitigates the environmental burden of food production but also paves the way for the development of integrated biorefineries based on local resources.

ABSTRACT. This research evaluated the effect of the organic load rate as % total solids and the influence of substrate/inoculum ratio on biogas and hydrogen production via dry anaerobic digestion. % total solids went from 21.8 to 30.3, and substrate/inoculum ratio conditions varied between 7 and 46.8. These conditions were evaluated in small reactors of 100 mL with a working volume of 50 mL at 37 C. Initial pH was adjusted to 7.8  0.2. The inoculum was anaerobic granular sludge from a wastewater treatment plant with a thermic treatment at 105 C. The substrate was the organic fraction of municipal solid waste from a municipal recycling plant. Higher total solids concentrations can achieve higher biogas productivities with a maximum of 1.8 Lbiogas/L/d and 44% hydrogen composition in biogas working with 30.3% of total solids. Substrate/inoculum ratio is a crucial operational parameter that impacts biogas and hydrogen production; despite the recommendation to work with low values of substrate/inoculum, we obtained biogas productivities between 1.6 – 1.8 Lbiogas/L/d with values of S/I ratio of 33.5 – 43.5 achieving H2 concentrations of 47%.

ABSTRACT. In low-income countries, 93 % of waste is disposed of in open dumps where methane is released into the environment from organic waste degradation without appropriate management. Organic waste can be valorized for bioenergy production, such as biohydrogen (bioH2). The purpose of this study was to compare the biohydrogen (bioH2) production via dark fermentation of the organic fraction of municipal solid waste (OFMSW) when a controlled intermittent feeding strategy based on biogas online monitoring is used in a sequencing fed-batch reactor (SFBR). Controlled feeding strategies ensure stable system operation by reducing risks of overloading, responding to accidental toxic feeding, preventing destabilization, and automatically setting process limits, such as hydraulic retention time. These simple strategies could effectively manage variations in the influent quality and are suitable for industrial processes when paired with easy-to-use monitoring sensors, such as biogas online measurements. Two SFBR (R1 and R2) were started up in similar conditions (cycle time of 24 h, 37 °C, working volume of 1.2 L, an exchange volume of 70 %) with OFMSW as substrate at 15 gVS/L supplied intermittently in eight pulses during the reaction phase. After 34 cycles, the controller was activated to decide when to supply the feeding pulses or when to stop the reaction time in R2. Seven cycles more were monitored with the same initial conditions (except for the cycle time in R2 that depended on the controller), and then R1 and R2 were subjected to disturbances in the organic loading rate in the influent. 5, 10, 15, 20, and 25 gVS/L of influent were randomly used to feed R1 and R2 to simulate natural variations in OFMSW. BioH2 production, productivity and yield were significantly higher in R2 in comparison with R1 when the controller was used. These results were consistent after multiple monitoring cycles even when the organic loading rate was purposely modified. COD and carbohydrates removal efficiency was lower in R1. It is possible that the controller facilitated hydrolysis at R2. Volatile fatty acids and organic acids composition in effluent suggest that many metabolic routes and microorganisms interactions contribute to the bioH2 production.

ABSTRACT. Design and Evaluation of Sr₂Ta₂O₇–Carbon Quantum Dots System for Enhanced Hydrogen Production by Photocatalytic Water Splitting R.Ahumada-Lazo, N.Apiquian-Ulloa,*C.L.Compeán-González, N.Delgado-Jiménez, M.Ponce-Ruiz, J.M. Ramírez-de-Arellano-Niño-Rincón, E.Saad-Barrientos. Instituto Tecnológico de Estudios Superiores de Monterrey, Anillo Perif. 6666, Coapa, San Bartolo el Chico, Tlalpan, Ciudad de México, CDMX, 14380. *Tel: +525514316392; e-mail: A01784464@tec.mx

ABSTRACT Photocatalysis has gained attention as a sustainable method for hydrogen production via water splitting, contributing to the development of green energy technologies. Among semiconductors used in photocatalytic water splitting, strontium tantalates (Sr₂Ta₂O₇) have shown potential due to their chemical stability and suitable band structure. However, like most semiconductors, Sr₂Ta₂O₇ exhibits limited hydrogen evolution activity without the assistance of a cocatalyst to extend light harvest and the number of exposed active sites, enhancing charge carrier separation efficiency and improving stability. Nevertheless, cocatalysts need to be selected carefully, as they need to work in synergy with the semiconductor to achieve this improvement. Carbon-based quantum dots (CQD’s), derived from organic matter, exhibit semiconductor properties and excellent light absorption capabilities, the reason why recently, hybrid photocatalysts containing carbon quantum dots (CQDs) have been proposed to solve associated problems with conventional photocatalytic systems. In this work Density functional theory (DFT) and experimental studies were performed to identify the interface characteristics of the heterojunction formation between Sr₂Ta₂O₇ and CQDs for the enhancement of photocatalytic hydrogen production. The interfacial electronic structure, charge transfer, and optical characteristics of the CQDs@ Sr₂Ta₂O₇ surface were simulated using DFT, ab initio calculations, and the pseudopotential formalism. We used the Quantum ESPRESSO code package, with the PBE XC functional expression. The XCrySDen package was used for crystal structure visualization. Experimental work focused on the cocatalyst loading system varying Sr₂Ta₂O₇:CQD ratios, followed by optical characterization. Variation of Sr₂Ta₂O₇:CQD ratios influence particle dispersion and size control as critical factors for maximizing surface reactivity. Both theoretical and experimental results were compared to confirm the enhanced optical absorption of the CQDs@ Sr₂Ta₂O₇ system, facilitating the use of solar light into the process. The results will provide insights into material design and process optimization, contributing to the development of next-generation green hydrogen technologies.

References: 1. Arias Velasco, V., Agudelo, A. C., Hotza, D., & Gómez González, S. Y. (2023). Context and prospects of carbon quantum dots applied to environmental solutions. Environmental Nanotechnology, Monitoring & Management, 20, 100884. https://doi.org/10.1016/j.enmm.2023.100884 2. C.L. Compean-González, V.M. Arredondo-Torres, M.E. Zarazúa-Morin, M.Z. Figueroa-Torres. “Effect of Strontium Tantalate Surface Texture on Nickel Nanoparticle Dispersion by Electroless Deposition” Journal of Alloys and Compounds. Volume 643, September 2015. Pages S80-S83. ISSN :0925-8388 DOI: 10.1016/j.jallcom.2014.10.154 3. C.L. Compean-González. (2014). Tesis: Dispersión de nanopartículas de níquel y rutenio por electroless sobre tantalatos de estroncio con diferente textura y su influencia en la fotoproducción de hidrógeno. Universidad Autónoma de Nuevo León. URI: http://eprints.uanl.mx/id/eprint/4453 4. Ghosh, D., Narzary, B., Bora, A. J., & Kalita, H. (2021). Current and future perspectives of carbon and graphene quantum dots: from synthesis to applications in energy conversion and storage devices. Materials Science in Semiconductor Processing, 123, 105523. https://doi.org/10.1016/j.mssp.2020.105523 5. Kazuya Nakata, Akira Fujishima. TiO2 photocatalysis: Design and applications, Journal of Photochemistry and Photobiology C: Photochemistry Reviews, Volume 13, Issue 3, 2012 Pages 169-189, ISSN 1389-5567, https://doi.org/10.1016/j.jphotochemrev.2012.06.001. (https://www.sciencedirect.com/science/article/pii/S1389556712000421) .

ABSTRACT. ZnAlFe mixed metal oxides (ZnAlFe MMOs) were synthesized from layered double hydroxides (LDHs) prepared by a one-pot coprecipitation method at pH 9 using an initial weight composition of Zn2+ = 75%, Al3+ = 15% and Fe3+ = 10%, with or without the addition of citric or oxalic acid. The resulting samples were characterized thoroughly by different techniques, including photoelectrochemical techniques to explain the photocatalytic behavior. Finally, the different MMOs were evaluated for photocatalytic hydrogen production via water reduction under visible light irradiation, four blue LED lamps (3 W) with λ =540 nm were used as the irradiation source. These LED lamps were properly distributed to ensure that the suspended solids were fully illuminated. The amount of hydrogen produced was measured using a Shimadzu GC-8A gas chromatograph equipped with a thermal conductivity detector (TCD) and a 5 Å molecular sieve column with nitrogen as the carrier gas. The XRD results demonstrated that all as prepared LDH samples had characteristic hydrotalcite phase and validated the formation of a well-crystallized layered structure. After calcination at 500 °C, the LDHs exhibited a sintered, broken-down morphology with the concomitant formation of a solid solution of MMOs with basic properties. The adsorption-desorption isotherms of the MMOs were categorized as type IV with H3 hysteresis, suggesting the presence of mesopores. The band gap values were 2.42 eV for ZnAlFe, 1.97 eV for ZnAlFe-Cit, and 1.77 eV for ZnAlFe-Ox MMOs. Photocatalytic hydrogen production tests reveal a favorable hydrogen evolution rate of 269.2 μmol h⁻¹ g⁻¹, followed by ZnAlFe-Cit (154.2 μmol h⁻¹ g⁻¹) and ZnAlFe-Ox (110.2 μmol h⁻¹ g⁻¹). This was attributed to the higher BET surface area of 165.3 m2/g for ZnAlFe compared to 142.5 m2/g for ZnAlFe-Cit and 63.8 m2/g for ZnAlFe-Ox MMOs, which lead to a better acceleration of the charge (e-/h+) transfer by increasing the number of surface reaction sites.

ABSTRACT. Currently, energy production and consumption seriously affect the environment because burning fossil fuels powers the main energy production systems, generating greenhouse gases such as carbon dioxide. Consequently, the scientific community is actively pursuing alternatives aimed at mitigating emissions generated during the combustion of fossil fuels, among which the utilization of green fuels, such as hydrogen, has emerged as a promising strategy. Current conventional hydrogen production methods involve carbon dioxide emissions, so they are betting on producing green hydrogen, obtained through catalytic processes. However, one of the main obstacles to the development of this technology is that it requires platinum catalysts, which are very scarce metal on the planet and therefore very expensive. For this reason, in this work, we propose to obtain catalytic materials from carbon-doped carbonitride with different C/N ratios. Graphitic carbonitride can absorb visible light due to its moderate band gap (~2.7 eV), which makes it worthwhile for photocatalysis. However, its low electrical conductivity and limited electron transfer restrict its performance in electrocatalytic systems. To overcome these limitations, we propose the carbon doping of these structures to improve electrocatalytic performance and thus enhanced photoelectrocatalytic properties for hydrogen production. The following procedure was used to obtain carbon-doped carbonitride: Bulk carbon nitride was mixed with different amounts of glucose to obtain different samples with different C/N ratios and left stirring with water for 12 h. The mixtures were dried at 120 °C for 12 h and subsequently calcined at 500 °C for 2 hours. The resulting materials were characterized by different spectroscopies (UV-Vis, XPS, IR), X-ray diffraction, nitrogen physisorption, thermogravimetric analysis (TGA), and electrochemical measurements. This study explores the physicochemical, optical, and structural properties of carbon-doped carbonitride structures as a function of their C/N ratio and their potential use as catalytic materials in photoelectrocatalytic systems for hydrogen production.

ABSTRACT. Photocatalytic water splitting has garnered significant attention as a highly promising and sustainable strategy for hydrogen production, harnessing abundant solar energy as a clean and renewable resource. This innovative process utilizes semiconductor materials that, upon photon absorption, generate electron-hole pairs capable of initiating and sustaining redox reactions essential for the efficient splitting of water molecules into hydrogen and oxygen gases—without the emission of harmful pollutants. In contrast to conventional hydrogen generation methods reliant on fossil fuels, photocatalysis offers a green alternative that aligns with global efforts toward carbon-neutral energy systems. The overall efficiency of this process is intricately linked to the optical and electronic properties of the photocatalyst, including its ability to absorb visible light and facilitate charge carrier separation. Consequently, the design and development of novel photocatalytic materials with tailored band structures and enhanced light-harvesting capabilities remain at the forefront of research. Moreover, computational simulation has emerged as a powerful tool to complement experimental efforts by enabling atomic-scale insights into material behavior, predicting key properties, and guiding the rational design of photocatalysts. This approach accelerates innovation by reducing experimental trial-and-error and optimizing material performance more efficiently. In this study, NiFe₂O₄/g-C₃N₄ heterojunctions were synthesized via a combined impregnation and photo-assisted anchoring method. Comprehensive characterization of both pristine materials and heterojunction composites was conducted through X-ray diffraction (XRD), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) surface area measurements, Hall effect studies, UV-Vis spectroscopy, transmission and scanning electron microscopy (TEM/SEM), and cyclic voltammetry. Photocatalytic hydrogen evolution was quantitatively assessed by gas chromatography in a quartz reactor illuminated by a 250-watt mercury halide lamp. Furthermore, radiative absorption and scattering coefficients were calculated for all materials, providing critical insights into their light-interaction behaviors. Comparative analysis revealed that the heterojunctions exhibited notably higher absorption coefficients and substantially enhanced hydrogen production compared to their pristine counterparts. This improvement is attributed to a pronounced redshift in the band gap energies induced by heterojunction formation, which significantly extends the visible light absorption range and promotes more efficient photogenerated charge separation. These findings highlight the promising potential of NiFe₂O₄/g-C₃N₄ heterostructures for advancing visible-light-driven photocatalytic hydrogen production.

ABSTRACT. The search for clean and sustainable energy sources has driven the development of technologies for hydrogen production by photocatalysis. Among these, semiconductors have proven to be key materials thanks to their ability to generate electron-hole pairs when irradiated with light. However, the efficiency of the process depends strongly on the individual properties of the materials used, such as light absorption in the visible spectrum, charge carrier mobility, specific surface area, and crystalline structure. This work focuses on the synthesis and detailed characterization of three pristine materials: titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and graphene oxide (GO), selected for their complementary properties for future applications in advanced photocatalytic systems. TiO₂ was synthesized by the sol-gel method using titanium butoxide as a precursor; CoFe₂O₄ was obtained by auto-combustion with metal nitrates and citric acid, while GO was prepared following the modified Tour method. Structural characterization by X-ray diffraction (XRD) confirmed the formation of the expected crystalline phases: anatase for TiO₂ and cubic spinel for CoFe₂O₄, while GO exhibited an amorphous structure with characteristic diffraction patterns. Transmission electron microscopy (TEM) revealed well-defined nanometric morphologies for each compound. UV-Vis spectroscopic analysis showed that CoFe₂O₄ exhibits higher absorption in the visible range, with an estimated band gap of 1.8 eV, compared to 3.2 eV for TiO₂. The specific surface area, determined by nitrogen physisorption (BET), was significantly higher for GO, exceeding 100 m²/g, while TiO₂ and CoFe₂O₄ presented mesoporous surfaces with intermediate values. Preliminary photocatalytic evaluation of the individual materials under visible irradiation showed that CoFe₂O₄ performed best in hydrogen evolution, attributable to its narrower band gap and higher absorption capacity in the visible range. TiO₂ showed moderate activity, limited by its wide band gap, while GO, as expected, did not produce H₂ directly, although its structure suggests high potential as a conductive medium in heterostructures. In conclusion, the three pristine materials exhibit valuable properties for the formation of Z-scheme hybrid systems, with CoFe₂O₄ standing out for its individual performance. These results establish a solid basis for the rational design of heterojunctions aimed at optimizing hydrogen production efficiency under sunlight, and contribute to fundamental knowledge about the specific role of each component in complex photocatalytic systems.

ABSTRACT. With fossil fuels dominating global energy demand, their associated greenhouse gas emissions pose a critical threat to environmental stability, aggravating the issue of climate change. To minimize irreversible changes and the socioeconomic impacts of fossil fuel depletion, energy diversification with low carbon emissions must be achieved. The transition toward a sustainable, low-carbon energy future has positioned hydrogen as a key vector in the global energy transition roadmap. Among various hydrogen production pathways, photocatalytic water splitting emerges as a particularly promising strategy due to its potential to directly convert abundant solar energy into clean hydrogen fuel. However, achieving high-efficiency solar hydrogen production requires continuous improvement of photocatalysts. Among these, graphitic carbon nitride (g-C₃N₄) has been identified as a promising material for solar fuel production due to its suitable band gap (~2.5 eV), excellent light absorption, thermo-physical durability, and tunable electronic structure. Nevertheless, its photocatalytic activity is limited by the short lifetime of charge carriers and a narrow visible light absorption range. To overcome these limitations, modification strategies involving the incorporation of transition metal-based compounds—such as NiO and Co₃O₄—have been investigated to increase charge carrier lifetime through heterojunction formation, enhance light absorption, and improve redox capabilities. In this work, g-C₃N₄-based materials with monometallic (Ni, NiO, Co₃O₄) and bimetallic (Ni–Co₃O₄) loadings were synthesized and characterized for hydrogen production under visible light. Pristine g-C₃N₄ (MCN) was prepared via thermal condensation of melamine, while metal-loaded samples—labeled as MCN-Ni, MCN-NiO, MCN-Co₃O₄, and MCN-Ni-Co₃O₄—were prepared via wet impregnation. FTIR spectra confirmed the presence of g-C₃N₄ before and after metal loading, with a characteristic vibrational band at 810 cm⁻¹ attributed to the out-of-plane bending of the tris-s-triazine units. XRD patterns revealed two prominent reflections corresponding to the layered structure of g-C₃N₄, along with additional peaks associated with face-centered cubic (FCC) NiO, Co₃O₄, and metallic Ni phases in the metal-supported samples. UV-Vis spectra showed band gap narrowing of g-C₃N₄ after Ni and Co₃O₄ addition, with a red shift in maximum absorption wavelength. Electrochemical measurements supported these findings, confirming a general narrowing of the band gap, along with shifts in both the conduction and valence bands. Nitrogen adsorption–desorption isotherms showed type IV profiles with H3 hysteresis loops for pristine MCN, indicative of interlayer porosity, while metal-loaded materials exhibited type III isotherms and reduced specific surface areas. Elemental mapping and energy-dispersive X-ray spectroscopy (EDS) indicated high metal dispersion on the photocatalyst surfaces. Photocatalytic water splitting under visible light showed enhanced hydrogen evolution across all metal-loaded samples, with MCN-Ni-Co₃O₄ being the most active, achieving 57 μmol/(h∙g_cat), over ten times higher than pristine g-C₃N₄. These preliminary results suggest that Ni and Co₃O₄ additions effectively improve charge carrier separation in g-C₃N₄, thereby enhancing photocatalytic performance.

ABSTRACT. Green energy solutions involving environmental benefits are required for a permanent future. P-MFC, or plant-based microbial fuel cells are a promising method of producing power by absorbing CO2 during biomass conversion. Additionally, by controlling temperature and improving environmental aesthetics, this technique enables green construction applications and sustainable agriculture. The crab shells are the primary source of chitin, the second most popular natural polymer. Its biodegradable and biocampatable derivative, Chitosan has heavy ability for permanent use. To improve the bioactivity and utility of the Callinectus sapidus (Blue Crab) shells, the task introduces a unique method to remove high purity nano-chitosan through nano-signs techniques. Two important uses for extracted nano-chitosan were as a proton-operating polymer in P-MFC as a biostimulant for the production of bioelectricity and to encourage plant growth. When compared to control, soil drenched studies showed a major increase in moisture content (39%), water-holding capacity (84%), total nitrogen (3.8 g/kg), and carbon content (48.4 g/kg), as well as significant growth in plant biomass, root-reduction and significant improvement in soil health. In addition, during tomato plant testing, the P-MFC combined with nano-chitosan performed better ionic conductivity, to reach the peak voltage of 1.5 V. These results show how nano-chitosan can be used to promote permanent agriculture and reproduction organic waste for use in renewable energy applications. To maximize performance and scalability and to open the door in a creative, environmentally responsible manner of energy production and agricultural stability, more research is required.

ABSTRACT. This work explores alternatives for modifying polymeric materials with the aim of obtaining polyelectrolytes with potential application in ionic conduction systems, such as fuel cells or brine electrolysis. The direct sulfonation of widely used resins in the plastics industry, such as acrylonitrile-butadiene-styrene (ABS) and high-impact polystyrene (HIPS), is investigated in order to introduce sulfonic acid groups into the polymer matrix. The chemical modification of ABS is carried out in 1,2-dichloroethane, with a reaction time of two hours, using fuming sulfuric acid as the sulfonating agent at a molar ratio of 150% relative to the real aromatic rings in the polymer. In the case of HIPS, sulfonation is conducted under similar conditions, but with a reaction time of five hours and a molar ratio of 100% with respect to its aromatic rings. The physicochemical and thermal characterization of the polymeric resins, as well as the resulting ionomers, are performed using Fourier-transform infrared spectroscopy (FTIR), proton and solid-state carbon-13 nuclear magnetic resonance spectroscopy (¹H-NMR and ¹³C-NMR), and thermogravimetric analysis (TGA). From these studies, the degree of sulfonation (DS), a key parameter associated with ionic conductivity, is determined through analysis of the ¹H-NMR spectra and through the characteristic mass loss of sulfonic groups by TGA. For the modified ABS, new vibrational bands are identified in comparison to the unmodified resin. However, its low solubility in deuterated solvents prevents a detailed analysis by ¹H-NMR. Therefore, solid-state ¹³C-NMR spectroscopy is employed, revealing signals that indicate an unwanted AN comonomer modification, further corroborated by TGA. In contrast, sulfonated HIPS shows characteristic FTIR and ¹H-NMR signals corresponding to sulfonic groups, and a mass loss associated with these functional groups in the TGA analysis. Nonetheless, the DS quantified by ¹H-NMR indicates a low sulfonation degree of approximately 4% relative to the aromatic rings, whereas TGA results suggest a value closer to 20%, such differences are discussed.

ABSTRACT. ABSTRACT Global warming, the depletion of fossil fuels, and environmental pollution are the primary reasons for the development of novel energy storage devices powered by renewable energy sources. In this work, blends of MnO2 with carbon nanotubes decorated with Pd nanoparticles (NPs) were studied, in order to evaluate the performance and the mechanism for the oxygen reduction reaction (ORR) and the hydrogen oxidation reaction (HOR). Which are cathodic and the anodic reactions that take place in anionic exchange membrane fuel cells (AEMFC). The metallic loading of Pd on the surface of the catalysts, the particle size, dispersion, and other physicochemical properties of the catalysts, were determined by TGA, ICP-OES, TEM, BET, and XRD, respectively. The MnO2 shows catalytic activity for ORR, however, the loading of Pd enhanced the catalytic kinetic parameter such as Eonset, E1/2 and Jlim. When the catalysts were mixed with carbon support a synergistic effect is observed, due to the ohmic resistance in the cell decrease. On another hand, pure MnO2 nanorods do not show catalytic activity towards HOR. When the NPs are deposited on the MnO2 exhibited catalytic activity. Finally, the blends were evaluated as anodic and cathodic electrocatalyst in an AEMFC. The Pd/MnO2: Pd/CNT showed a value of J of 197 mA cm-2 when used as cathodes. When the materials are used in the anode the value of Jlim increases. The flooding of the cell was observed, the low porosity of catalyst led to the generation of large amounts of water, decreasing the performance of the fuel cell.

ABSTRACT. Microbial fuel cells are systems that generate electricity by utilizing the metabolic processes of microorganisms naturally present in the soil. This study presents the design and evaluation of a modular and stackable energy generation system that incorporates plants from the Helianthus annuus species, commonly known as sunflower, as biological support. The objective is to increase the efficiency of electricity production while contributing to the improvement of soil quality. To assess and optimize the system’s performance, a series of environmental sensors were integrated to continuously monitor critical variables, including the concentration of essential soil nutrients such as nitrogen, phosphorus, and potassium, as well as soil moisture levels, acidity level measured by pH, and temperature. Additionally, a computational model known as an artificial neural network—designed to replicate the learning capacity of biological neurons—was developed to predict the amount of electrical energy that the system can produce under different environmental conditions. This dual-purpose system serves both as a source of renewable energy and as a decision-support tool for environmentally responsible farming. By providing real-time information about soil conditions and energy output, the system enables farmers to adopt precision agriculture strategies, improving crop productivity while minimizing the environmental impact associated with the overuse of water and chemical inputs. Furthermore, due to its modular structure and predictive functionality, the system can be adapted for use in a variety of rural and agricultural settings, particularly in areas with limited access to conventional energy infrastructure. Its potential integration with other sustainable technologies, such as those involving hydrogen-based energy solutions, positions it as a promising component of future hybrid renewable energy systems. This research advances the digital transformation of bioelectrochemical technologies and offers a practical, scalable approach to combining biological systems, environmental data acquisition, and intelligent predictive modeling in support of sustainable development and the transition to clean energy sources.

ABSTRACT. The efficient production of hydrogen by alkaline electrolysis depends to a large extent on the performance and stability of the electrodes used, since they represent approximately 50% of the total cost of the equipment. In this work, the behavior of nickel coatings applied on different metallic materials is studied. These electrodes will be used in an alkaline electrolyzer designed to optimize its performance in concentrated alkaline solutions, specifically with 30% potassium hydroxide. The nickel coating improves corrosion resistance, increases electrical stability and extends electrode life. A comparative analysis was made between different materials for possible coating: copper, aluminum, iron, carbon steel and stainless steel. For each one, the properties before and after the nickel plating process were evaluated, observing significant improvements in conductivity, wear resistance and electrochemical behavior. The specific challenges of nickel plating were also identified according to the type of material, such as the need for pre-treatment in the case of aluminum and stainless steel (Wood bath). Mohammad Mehdi Tavallaie et. al. conclude that the morphology of the produced Ni–Cu–Fe coatings was completely affected by the coating parameters in the deposition bath and the type of substrates. In samples with micro/nano-cone morphology, deposited at a constant current density of 2.5 A/dm2, better HER behavior was obtained due to the highly effective surface and easier separation of hydrogen bubbles. The results allow establishing technical criteria for the selection of materials and operating parameters of the nickel plating process, which has a direct impact on the efficiency of alkaline electrolysis systems for hydrogen production. It was observed that the coatings made on copper substrates showed superior adhesion and greater uniformity compared to those obtained on carbon steel and stainless steel. Additionally, tests were carried out at different current densities, identifying that from 0.3 A/cm² defects began to appear in the nickel deposit. Among these defects were found poor adhesion of the coating, formation of dendritic structures or “ramifications” on the edges of copper and carbon steel parts, as well as a lack of effective deposition on the stainless steel surface.

ABSTRACT. Solid Oxide Fuel Cells (SOFCs) are electrochemical devices that directly convert chemical energy into electricity through the oxidation of a fuel, typically hydrogen or light hydrocarbons. Their energy efficiency surpasses that of conventional conversion systems, and their high operating temperatures (between 800°C and 1000°C) make necessary the use of advanced ceramic materials as components. These characteristics make them highly attractive for stationary power generation and sustainable energy systems. This work reports the synthesis of materials based on lanthanide- and calcium-doped ceria, with a global doping level of up to 24% mol, in a system composed of CeO2 and Gd, Nd, Y, Sm, and Ca oxides, the latter used as a sintering aid. To understand the effect of cationic substitution within the system, a comparison is made between different doping concentrations and their impact on the material’s structure and properties. The synthesis of these materials was carried out using the mechanochemical method, a high-energy milling technique that promotes chemical reactions through plastic deformation and the generation of structural defects in solid reactants. This method is particularly useful for obtaining dry-route materials and enhancing reactivity in multicomponent systems such as those studied in this work. Subsequently, the samples underwent heat treatment at 1200°C to promote the crystallization of the desired phases and achieve the sintering of the pellets, which were later analyzed. A fluorite-type structure was successfully obtained, confirmed by X-ray diffraction (XRD), a technique used to evaluate the evolution of synthesis as a function of milling time and heat treatment temperature. Additionally, the densification of sintered pellets at 1200°C was analyzed by determining their relative density, through experimental density measurements, using the Archimedes method, and calculating theoretical density, based on lattice parameter determination. This information was obtained through the analysis of data extracted from X-ray diffraction patterns. The electrical properties were studied by impedance spectroscopy in a temperature range of 350 to 600°C, showing values comparable to those previously reported by other authors. Scanning Electron Microscopy (SEM) images using secondary electrons (SEI) were included to observe surface topology. Additionally, Energy Dispersive Spectroscopy (EDS) analyses were carried out for qualitative elemental composition analysis, in this case, to rule out the presence of contaminant elements. The results indicate that these materials are suitable for application as electrolytes in SOFC, highlighting their cubic crystalline structure and favorable electrical properties.

ABSTRACT. Microbial Fuel Cells (MFCs) constitute a promising technology for renewable energy generation and efficient wastewater treatment. In the present work, it was optimized the electrodeposition of MnO2 on stainless steel mesh was optimised, which was used as cathode in the plug-in type MFCs. A Taguchi experimental design was used to optimize the electrodeposition conditions, such as concentration of chemical reagent, time, temperature, and voltage, followed by the detailed characterization of the electrodeposited mesh with better electrical conductivity. The results revealed a significant increase in electrical conductivity and confirmed the presence of MnO2 on the mesh after electrodeposition. MFCs equipped with these improved cathodes showed remarkably superior performance in terms of voltage, current density, and power density as compared to mesh without treatment. These findings highlight the potential of MnO2 electrodeposition on stainless steel meshes to optimize energy generation efficiency in MFC and advance the sustainability of wastewater treatment by removing 84% of total organic matter. This integrated approach drives the practical application of MFC technology as a dual solution to energy and environmental challenges.

ABSTRACT. This work aims to identify sustainability criteria and indicators applicable to the production of renewable hydrogen (H2R) reported in the scientific literature, and to select those most relevant to the national context, as well as to evaluate three projects currently underway in Mexican territory. To achieve this, a systematic review of academic literature was conducted, focused on the search and analysis of sustainability criteria and indicators, complemented by the use of gray literature (news articles, press releases, and institutional reports) to identify and characterize H2R projects that have been announced or are already in operation in the country. As a result, thirteen dimensions of analysis and a total of 214 sustainability criteria were identified, with economic, environmental, and technological/technical categories being the most frequently cited. For application to the national context, criteria corresponding to the environmental, social, economic, and energy transition dimensions were selected, as they together provide a comprehensive framework for evaluating the sustainability of the projects. Regarding the project landscape, 24 announcements were identified, although only 19 had publicly available and verifiable information. Based on the selected criteria and indicators, three projects to be developed in the national territory were evaluated, located in the states of Nuevo León, Guanajuato, and Baja California Sur (B.C.S.). The evaluation yielded mixed results, with the project in B.C.S. receiving the highest sustainability rating. It is important to note that the identified criteria and indicators are not intended to replace existing legal requirements, but rather to complement aspects where specific regulation is still lacking and where they can strengthen a sustainability-oriented approach. Although H2R represents a promising alternative for the decarbonization of the economy, its development may also involve significant impacts on land and communities, which must be carefully considered from the proposal and operational phases through to project closure.

ABSTRACT. In accordance with the United Nations Sustainable Development Goals (SDGs), transitioning toward sustainable and decentralized energy systems is a key strategy for improving the quality of life in rural communities, particularly those in environmentally vulnerable areas such as the shores of Lake Pátzcuaro in Michoacán, Mexico. This paper presents a technologically viable proposal for green hydrogen production, primarily using water hyacinth (Eichhornia crassipes) alongside locally available organic waste, woody debris, and agricultural residues. The proposed system involves an initial biomass conversion process designed to operate under conditions adapted to the variability and heterogeneity of regional feedstocks, followed by green hydrogen generation.

The methodology includes an analysis of the energy potential of available waste in lakeside communities, a characterization of biomass conversion processes, and an estimation of net hydrogen production. The technical and economic feasibility of implementing this system at a community scale is evaluated. Results indicate that water hyacinth—an invasive species in the lake ecosystem—contains recoverable energy through thermal pretreatment and blending with agricultural waste. The estimated hydrogen output could meet local energy demands for cooking, lighting, and light mobility (transport boats), while mitigating environmental issues linked to hyacinth overgrowth and uncontrolled waste burning.

Finally, the environmental, social, and economic impacts of the project are discussed, highlighting its potential to reduce fossil fuel dependence, create local employment, and contribute to the ecological restoration of Lake Pátzcuaro. This research proposes a replicable model for energy self-sufficiency based on local resources, aligned with circular economy principles and environmental justice.

ABSTRACT. The United Nations Sustainable Development Goals emphasize the transition to green energy sources to mitigate adverse climate impacts. Mexico possesses abundant solar and wind resources, offering a strong potential for green hydrogen production. However, nationwide studies that systematically integrate renewable energy availability, water resource constraints, and environmental protection remain limited. Existing assessments often focus on specific regions, individual renewable sources, or omit critical sustainability factors, potentially leading to overestimations of feasible production capacities. This study presents a comprehensive geospatial approach to estimate the theoretical potential for green hydrogen production across Mexico, integrating renewable energy distribution, groundwater constraints, and environmental considerations. Renewable energy availability was characterized using SolarGIS and the Mexican Wind Atlas datasets, harmonized under a common spatial projection to ensure consistency. Groundwater data from the National Water Commission (CONAGUA) was incorporated, acknowledging water as a critical input for hydrogen production via electrolysis. Natural Protected Areas were excluded through a spatial mask based on the official dataset provided by the National Commission for the Knowledge and Use of Biodiversity (CONABIO), which compiles federally designated conservation zones. The potential of hydrogen output was calculated by combining the available renewable energy with typical electrolyzer efficiencies. Subsequently, the associated water demand was estimated and compared against local groundwater reserves. Zones where groundwater availability was insufficient to support the required electrolysis were systematically excluded, ensuring that the final estimation accounts for both energy and water sustainability. Beyond a basic theoretical estimation, a feasibility-based spatial selection approach was applied. Multiple production scenarios were considered: selection of all suitable areas, focusing on the top 50 percent and top 25 percent based on energy potential, and a constrained scenario where hydrogen productivity was limited within defined lower and upper thresholds. In the constrained case, hydrogen production exceeding the upper threshold was adjusted to match the defined maximum value, aiming to reduce water demand pressure and promote a more balanced production distribution across regions. The developed methodology contributes to the national understanding of green hydrogen potential by integrating energy and water resource sustainability considerations. It establishes a basis for future analyses focused on refining site selection strategies and supporting the development of environmentally responsible hydrogen production initiatives.

ABSTRACT. Energy resources have always driven the geopolitical dynamics around the world. Since the Uniden Kingdom leadership with whale oil in the mid-1700s to early 1800s. Then, coal, oil and natural gas came to replace it and with that a new leadership through other actors. Nowadays, the world’s economic and technological growth and a new, modern way of life, has led to high energy demand and consumption society, provoking the current climate crisis. At the same time, the international framework has identified renewable energies as the answer to the environmental issues. However, the so far results of the energy transition and the uncertainties of the sector must have a heavy impact in future energy choices and to geopolitical changes. Renewable energies represent 13% of the primary energy mix, however if hidroenergy and bioenergy are removed since these energy sources have had a low growing rate in the recent years, the remaining renewable energies (solar, wind and geothermal) only represent 2.89% of the mix, with an annual growing rate of 7%. However the energy demand is growing at record rates, where fossil fuels maintained an 85% share of total primary energy consumption, and in consequence the Green house emissions have reached the maximum historical in 2023. In recent years Green hydrogen is commonly proposed as the solution to renewable energy storage, integration and diversification. In general words, this technology can seem simple, use renewables energies to produce green hydrogen through electrolysis of water, and store it to use later on to generate power during periods of electrical peak demand, or use directly in industrial applications. The advantages of green hydrogen are based on the use of a renewable source and that it does not generate CO2 when burnt. However there are multiple challenges to be addressed before green hydrogen can have a significant representation in the energy transition, between the main challenges we have to consider the low efficiency of the electrolysis process, the cost of electrolysis and the need of additional energy to desalinize or purify water, storage and transport of large amounts of hydrogen is significantly expensive and green hydrogen production also needs a reliable source of energy as well. All energy carriers, including conventional fossil fuels, encounter efficiency losses each time they are generated, converted or used. In the case of hydrogen, these losses accumulate across different steps in the production chain. Mexico geographical conditions present a series of opportunities to explore the green energy industry, like the availability of multiple renewable sources than facilitate the creation of hybrid systems with a more continuous and steady flow of energy, and the multiple access to coast for the construction of desalination facilities, the multiple national and international actors interested in support the green hydrogen implementation have to be considered as well. The big challenge is to created a structure to improve green hydrogen generation and utilization, this structure includes public policies, bilateral cooperation and development programs, however any improvement should be made without compromising critical resources as water, has to consider the existing demand of hydrogen mainly for the petrochemical industry, the vulnerability of local communities and promote the creatin national technology. Create an economy and society that can actually relay on green hydrogen will define the future of countries, including the energy sovereignty and energy security. This article studies the current energy strategies in Mexico focus in green hydrogen, and establish improvement and opportunities recommendations to move forward, however is critical to identify the technical and geopolitical limitations, in order to create a realistic strategy.

ABSTRACT. Hydrogen is the most abundant element in the universe and is found freely in nature in compounds such as water. To obtain this energy vector, various production processes are employed, each labeled with a distinctive color: grey hydrogen, produced via steam methane reforming; blue hydrogen, obtained through natural gas steam reforming with sequestered carbon; pink hydrogen, generated via water electrolysis using nuclear energy; brown hydrogen, derived from coal gasification; and green hydrogen, produced through water electrolysis powered by renewable electricity. The latter is of greatest interest, as it is sourced from a renewable and non-polluting resource, classifying it as a clean energy generator.

The research, generation, production, and consumption of green hydrogen are gaining increasing relevance in Mexico. It is positioning itself as a clean resource and a cornerstone in the transition toward a low-carbon economy, reducing dependence on fossil fuels and enhancing energy security. Despite requiring significant investment, Mexico is in a development phase, with 24 clean hydrogen projects backed by an investment of $21.227 billion USD, projected to produce 196,702 tons of green hydrogen.

While large corporations such as CFE, CEMEX, PEMEX, and Tango Solar are leading hydrogen production, achieving widespread generation must begin at the foundational level—through university education. Thus, it is essential to analyze Mexico’s academic offerings in related fields, including Chemical Engineering, Civil Engineering, Electrical Engineering, Mechanical Engineering, Energy Engineering, and even business programs. Reviewing a university’s curriculum is critical when selecting a degree, as it provides a detailed structure, focus, and objectives of the academic program, allowing students to compare different programs and assess alignment with their interests and career goals.

This study facilitates such decision-making by compiling a comprehensive registry of Mexican universities with energy-related programs whose curricula cover topics such as hydrogen production, new techniques, efficiency improvements, cost reduction, infrastructure, storage, and transportation. Additionally, it highlights the absence of specialized green hydrogen degree programs, demonstrating that no universities currently offer dedicated undergraduate programs in this field. Students can only specialize through master's degrees, diplomas, or short courses—meaning they must first complete a foundational degree in engineering, chemistry, or energy before pursuing further training.

This gap underscores the need for curriculum modifications or even the creation of new academic programs, such as a Green Hydrogen Engineering degree, to advance expertise in this innovative and revolutionary clean energy field.

Some technical limitations are evident in the lack of a program specifically focused on Green Hydrogen; other limitations are the limited reach of these universities for the Mexican population. Having a specialized hydrogen program impacts the country's geopolitics by improving the training of future specialists who will take charge of the future transition to renewable energy.

The energy strategies Mexico is pursuing focus on hydrogen research and generation. Currently, the Mexican government is focused on providing new investments for clean energy generation projects. Within renewable energy, green hydrogen promises to be one of the energy leaders seeking to displace traditional producers such as oil and gas.

Making these transitions would position the country as a technological and economic competitor, as China and the United States do. Remembering that whoever can control this new technology can have geopolitical influence, as happened with oil and the dollar. Furthermore, energy dependence could be achieved if Mexico achieves a rapid pace of technological adoption, covers production and transportation costs, and adequately trains its engineers in schools.

ABSTRACT. In response to climate change, many countries—including Mexico—have committed to reducing their greenhouse gas emissions through international agreements such as the one reached at the 2015 Conference of the Parties (COP21) in Paris. As a result of these commitments, Mexico enacted the General Law on Climate Change, which aims to achieve a 50% reduction in emissions by 2050, relative to the levels recorded in the year 2000 [1]. This goal presents a significant challenge, particularly considering that Mexico is a country with a population of 124 million and an annual final energy consumption exceeding 5,000 PJ [2].

Within the national energy demand, the Industry and Transport sectors pose critical challenges for decarbonization. Transitioning these sectors to renewable energy sources and electrification is particularly complex due to the high-temperature requirements of industrial processes and the need for portable, energy-dense fuels in transportation. These characteristics underscore the importance of exploring alternative low-carbon energy carriers, such as hydrogen. Hydrogen has been widely studied as a key enabler of global energy decarbonization, as it can serve as a vector for renewable energy—offering the ability to transport, store, and manage energy demand, much like a battery, while also functioning as a fuel.

This work aims to present prospective future scenarios to 2050 that explore the potential of hydrogen to contribute to the decarbonization of the National Energy System (NES). This analysis was carried out by modeling the entire National Energy System (NES) using the Low Emissions Analysis Platform (LEAP). The model structures the NES into four major components: (1) national demographic and macroeconomic context, (2) energy demand, (3) energy transformation and transmission, and (4) available resources and international energy exchange.

After considering the technical specifications of hydrogen production and transformation processes, its potential applications across demand sectors, and the availability of resources for its generation, two scenarios were developed: (1) a Business-as-Usual (BAU) scenario, in which—consistent with current trends—hydrogen does not play a role in the NES; and (2) a Decarbonization (DEC) scenario, which proposes a deep decarbonization of the NES through the integration of renewable energy and hydrogen, aiming to meet 100% of national energy demand with clean energy sources.

Preliminary results indicate that, as expected, while hydrogen accounts for 0% of the Total Final Energy Consumption (TFEC) in the BAU scenario, it covers 18.92% of national energy demand in the DEC scenario. Similarly, while emissions from the NES exceed 1,000 MtCO₂e by 2050 under the BAU scenario—completely missing the targets set by the National Climate Change Strategy [3]—they reach net zero in the DEC scenario for the same year.

Although this study does not address the economic aspects of the proposed scenarios, it presents a technically feasible future that can be set as a goal to be pursued during the design and development of strategies to accomplish the energy transition of the National Energy System.

[1] Congreso de la Unión, (2012), Ley General de Cambio Climático, Mexico City, Mexico, Diario Oficial de la Federación, pp. 1–64. [2] SENER. (2019), Balance Nacional de Energía 2019, Mexico City, Mexico, Gobierno de México, Secretaría de Energía, pp. 28, 43. [3] INECC (2024). Evaluación de Estrategias de Descarbonización para la Actualización de la Estrategia Nacional de Cambio Climático de México. https://www.gob.mx/cms/uploads/attachment/file/921441/05_2024_Informe_Modelaciones_110624_v7.pdf