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AbstractThis study aims to optimize hydrogen (H2) production via ethanol steam reforming (ESR) and water gas shift reaction (WGSR) pathways, focusing on minimizing CO, CO2, and CH4 emissions while maximizing H2 yield. Employing Taguchi grey relational analysis, we investigate the intricate balance between production conditions and multi-response gas generation. Utilizing Origin Pro software, regression modeling forecasts individual and overall gas generation. Our analysis identifies optimal conditions: a feed liquid flow rate of 2 mL/min, water-to-carbon ratio of 3, ESR temperature of 300 °C, and WGSR temperature of 350 °C. These conditions promise clean, efficient H2 production. Key results show the water-to-carbon ratio and ESR temperature contributing 59.22% and 32.69% to production conditions' impact, respectively. Graphical and mathematical models validate these findings. Moving forward, further experimental validation of optimal conditions for multi-response gas generation is recommended. This study pioneers a transformative approach towards sustainable, environmentally friendly H2 production.

Introducing molecular dopants in carbon nitride has been shown to dramatically modify its electronic structure, resulting in efficient charge separation and improved photocatalytic efficiency. Herein, we have studied the effect of doping carbon nitride with 2-aminothiophene-3-carbonitrile. A fundamental photoelectrochemical characterization has been performed comparing the behavior of the resulting material (ATCN) with undoped carbon nitride (CN). On the one hand, it is shown that the photocurrent onset shifts with the pH up to a value of 8 for both materials, as expected theoretically. On the other, ATCN, which benefits from additional light absorption, shows an improved photoactivity toward hydrogen evolution. In addition, it displays intriguing photoluminescence properties that can be additionally engineered by modulating the potential. In a more general vein, this study illustrates how to shed light on the effects of introducing molecular dopants in the CN matrix. ; We are grateful to the Spanish Ministry of Education and Competitiveness for financial support through projects MAT2012-37676 and MAT2015-71727-R (co-financed with FEDER funds by the European Union). A.-K.D.G. thanks the Mexican government (CONACYT) for the award of a doctoral grant.

The "hydrogen energy station" is one method of hydrogen production at small and medium scales. Unlike more conventional hydrogen station designs where hydrogen is simply delivered or produced on-site with a fuel "reformer" or water electrolyzer and then compressed and dispensed, energy stations would provide multiple functions in the same facility. They would integrate systems for production of electricity for 1) local uses and/or the utility grid, 2) re-use of thermal energy "waste heat" for building heating/cooling needs, and 3) purified hydrogen for refueling vehicles. Hydrogen energy stations can be of various types and configurations. Most designs to date are based around some type of fuel cell power plant for electricity production, with coproduction of hydrogen either by splitting the stream of hydrogen from a fuel reformer or electrolyzer (to power the fuel cell and provide electricity with one stream and to refuel vehicles with the other) or by using excess hydrogen from the fuel side of the fuel cell system to provide vehicle fuel. A few hydrogen energy station demonstration projects have been conducted in the past few years, and additional projects are anticipated as part of the California Hydrogen Highway Network initiative and other regional distributed power and hydrogen fuel efforts. We suggest that the interest in hydrogen as a transportation fuel offers opportunities for the development of additional hydrogen energy station projects, as we are beginning to see in California. Promoting new projects such as these will allow for the more complete exploration of the varying potential of different designs, configurations, and locations/settings for the energy station concept. Clean Energy Group (CEG) commissioned this report in order to support the Public Fuel Cell Alliance project (PFCA) and to more fully explore the potential for hydrogen energy stations to play an important role in advancing the development of clean and efficient technologies for both stationary and transportation applications. The following are several recommendations for consideration by key stakeholders that have an interest in developing strategies for promoting these new technologies and projects. These recommendations are intended initially for consideration by state clean energy funds. While it is clear that there is no simple, one-size-fits-all program for state action, these are intended to serve as a starting point for in-depth discussions that can lead to state-specific action plans and stakeholder engagement processes. Specific recommendations include: * Integrate Energy Stations Into State Hydrogen Plans: Many states have completed or are undertaking to develop hydrogen "roadmaps." These state-specific plans, which have been completed in California, Ohio, New York and Florida, provide recommendations to capture new economic development opportunities related to hydrogen and fuel cell technologies. Other states, such as Massachusetts and Connecticut, are embarking on similar planning exercises. The energy station concept should be integrated into these existing and emerging hydrogen plans. California, for example, is emphasizing the inclusion of energy station projects in early hydrogen stations for its Hydrogen Highway effort. We believe this is a strategy that can be replicated in other states. * Explore Fleet-Based Opportunities to Deploy Energy Stations: In many settings, there likely exist opportunities for states to deploy energy stations in conjunction with a specific, clustered vehicle fleet. Fleet-based opportunities reduce the need to develop regional networks of refueling stations as envisioned in many "hydrogen highway" proposals and could be implemented in partnership with military, industrial and delivery organizations. In these settings, a single energy station could support the refueling demands of a significant vehicle fleet. Initially, in order to advance these opportunities, state clean energy funds and economic development offices could support and conduct opportunity assessment studies that identify specific fleets, partners and electricity demands. * Foster Public-Private Partnership Development: Energy stations, in order to be successful, require significant partnerships with technology providers and host facilities. These partnerships can be fostered through public support from state clean energy funds, economic development offices and other key players. In particular, funding and support of coalition-building processes can have cross-cutting benefits for other hydrogen-related priorities in specific states. * Proactively Address Regulatory Incentives: Advanced energy technologies require advanced regulatory policies. Many states have implemented regulatory preferences and incentives (such as standby charge exemptions and net metering policies) that recognize and accommodate the public preference for and benefits from fuel cell, hydrogen and clean energy technologies. The regulatory strategies used by these early leaders can be replicated in other states. This kind of support is especially important for energy stations where a key component of the project is providing distributed electricity for the electric grid. Currently, many regulatory barriers prevent the wide-scale adoption of clean distributed generation and limit the ability to quickly site energy stations. State clean energy funds and others can assist by facilitating information-sharing about the best model regulations that can overcome barriers to distributed generation facilities. * Develop Compelling Communications Strategies: The concept of using hydrogen in consumer settings has been plagued with public misperceptions and lack of awareness of the significant potential benefits and remaining challenges. In recent years, many states have conducted sophisticated consumer and stakeholder research that has resulted in new communications campaigns to increase public understanding and support for clean energy technologies. Many states, for example, recently joined together to develop and fund a "Clean Energy: It's Real, It's Here, It's Working. Let's Make More" branding campaign. This kind of proactive communications strategy would yield tremendous results for the hydrogen sector, helping to organize currently disparate enthusiasm for hydrogen with a single, compelling message while also helping to manage expectations regarding the types and timing of hydrogen technologies that are likely to be introduced.

As European countries continue to adapt their economic, social and industry policies to minimise the impacts of the COVID-19 pandemic, key elements of the Green Deal offer new jobs and business opportunities to help with the recovery while addressing climate change at the same time. In particular, the European Union (EU) hydrogen and energy system integration strategies clearly highlight the potential benefits of and urgent need for investment to accelerate the deployment of renewable electricity generation on which decarbonisation of the EU economy, including the future production of renewable hydrogen and synthetic fuels in the EU, will depend. In this Commentary, EASAC (the European Academies' Science Advisory Council), which is the independent voice of the National Academies of Science of the EU Member States, Norway, Switzerland and the UK, draws upon its previous work on energy and decarbonisation policies to comment and advise, through 15 key points for policy-makers, on the implementation of the EU hydrogen strategy. Now is the right time to begin a phased approach to the sustainable development, production and use of renewable hydrogen. Strong governance of the emerging renewable hydrogen sector and the removal of market barriers in the EU is needed, with good coordination between EU and Member State strategies and rules. Targeted investments in decentralised electrolysers should focus on further cost reductions and feeding renewable hydrogen into sustainable local markets and networks. For the foreseeable future, hydrogen should be used primarily for decarbonising those applications that are difficult to electrify. The EU should build a strong leadership role in global hydrogen markets, by developing international partnerships with third countries to include not only collaboration on research and technology development but also the trading of hydrogen production technologies, renewable hydrogen and synthetic fuels. Further studies and demand-driven initiatives, including research, should be initiated soon at EU and national levels to address the emerging and long-term needs for hydrogen infrastructure, standards and certification. EASAC calls on the EU to establish science-based long-term energy and climate policies that will remove market barriers and build investor confidence in the production and use of renewable hydrogen.

The article offers a conceptual vision of the development of the energy market based on the principles of sustainability, which should be characterized by safety, environmental friendliness, adaptability and stability, efficiency (including economic) and accessibility (including social), transparency. The importance of ensuring the adaptability of the development of the energy system due to uneven energy consumption throughout the day and throughout the year, stability, safety of energy generation, and transparency is substantiated, which will be facilitated, among other things, by the synchronization of the energy system of Ukraine with the energy system of continental Europe. The expediency of increasing the use of ecologically neutral sources of electricity, which is important for ensuring sustainable development, is substantiated . The possibilities and features of the development of energy generation from renewable sources are characterized, which include: solar, wind, hydrogen generation , the use of biogas, obtaining energy from household waste, as well as hydrogen and nuclear generation. Despite the ecological neutrality of solar and wind power plants, the need for disposal and processing of individual components at the end of their service life is described, the need to work out such issues in advance, which corresponds to the principles of sustainability. The adaptability of the operation of hydropower plants and their different productivity depending on the methods of using water energy are noted. The types of hydrogen production and the features of hydrogen generation are described, as well as the feasibility of developing biogas energy generation, which will contribute to the "smart" disposal of waste and the rational use of such resources. The dangers associated with nuclear power plants are summarized, the leveling of which will contribute to the safety and stability of their operation. Attention is also paid to types of energy generation that are not environmentally friendly (thermal power plants), which generate electricity by burning fuel (coal, gas). Their share in the energy-generating balance is decreasing, but today they still provide the necessary adaptability in the energy market. To ensure stable, adaptive, efficient operation of the energy market of Ukraine, it is important to ensure the diversification of generation; to maximally realize the potential for the use of renewable energy sources, to generate ecologically clean energy. Keywords: energy generation, ecology, environmental friendliness, stability, adaptability, sustainable development, energy market, energy security.

This paper concerns the economic and environmental challenges confronting California and the potential role for clean energy systems and hydrogen as an energy carrier in helping to address these challenges. Hydrogen in particular has recently gained great attention as part of a set of solutions to a variety of energy and environmental problems — and based on this potential the current high level of interest is understandable. In our view, however, full realization of the benefits that hydrogen can offer will not be possible without a clear strategy for producing hydrogen from clean and sustainable sources and in a cost-effective manner. One of hydrogen's greatest benefits — having a wide range of potential feedstocks for its production — also complicates the issue of how hydrogen use may be expanded and necessitates careful forethought as key technology paths unfold. We must remember that the additional cost and complexity of building a hydrogen infrastructure is only justified if significant benefits to society are in fact likely to accrue.This paper has been written for two primary purposes. First, we argue that the time is ripe for an expanded science and technology initiative in California for clean energy development and greater end-use energy efficiency. This initiative should span transportation systems, electrical power generation, and natural gas and other fuel use, and should place the potential for expanded use of hydrogen within this broader context. Second, we specifically discuss potential concepts and strategies that California might employ as it continues to explore the use of hydrogen in transportation and stationary settings. The authors believe that at this stage the question is not if California should continue with efforts to expand hydrogen use, because these efforts are already underway, but how these efforts should be structured given the level of effort that ultimately emerges through various political and corporate strategy processes. However, we feel that it is critical that these efforts take place in the context of a broader "no regrets" clean energy strategy for California.

This paper concerns the economic and environmental challenges confronting California and the potential role for clean energy systems and hydrogen as an energy carrier in helping to address these challenges. Hydrogen in particular has recently gained great attention as part of a set of solutions to a variety of energy and environmental problems — and based on this potential the current high level of interest is understandable. In our view, however, full realization of the benefits that hydrogen can offer will not be possible without a clear strategy for producing hydrogen from clean and sustainable sources and in a cost-effective manner. One of hydrogen's greatest benefits — having a wide range of potential feedstocks for its production — also complicates the issue of how hydrogen use may be expanded and necessitates careful forethought as key technology paths unfold. We must remember that the additional cost and complexity of building a hydrogen infrastructure is only justified if significant benefits to society are in fact likely to accrue. This paper has been written for two primary purposes. First, we argue that the time is ripe for an expanded science and technology initiative in California for clean energy development and greater end-use energy efficiency. This initiative should span transportation systems, electrical power generation, and natural gas and other fuel use, and should place the potential for expanded use of hydrogen within this broader context. Second, we specifically discuss potential concepts and strategies that California might employ as it continues to explore the use of hydrogen in transportation and stationary settings. The authors believe that at this stage the question is not if California should continue with efforts to expand hydrogen use, because these efforts are already underway, but how these efforts should be structured given the level of effort that ultimately emerges through various political and corporate strategy processes. However, we feel that it is critical that these efforts take place in the context of a broader "no regrets" clean energy strategy for California.

An uninterrupted chain of energy supplies is the core of every activity, without exception for the operations of the North Atlantic Treaty Organization. A robust and efficient energy supply is fundamental for the success of missions and a guarantee of soldier safety. However, organizing a battlefield energy supply chain is particularly challenging because the risks and threats are particularly high. Moreover, the energy supply chain is expected to be flexible according to mission needs and able to be moved quickly if necessary. In line with ongoing technological changes, the growing popularity of hydrogen is undeniable and has been noticed by NATO as well. Hydrogen is characterised by a much higher energy density per unit mass than other fuels, which means that hydrogen fuel can increase the range of military vehicles. Consequently, hydrogen could eliminate the need for risky refuelling stops during missions as well as the number of fatalities associated with fuel delivery in combat areas. Our research shows that a promising prospect lies in the mobile technologies based on hydrogen in combination with use of the nuclear microreactors. Nuclear microreactors are small enough to be easily transported to their destinations on heavy trucks. Depending on the design, nuclear microreactors can produce 1–20 MW of thermal energy that could be used directly as heat or converted to electric power or for non-electric applications such as hydrogen fuel production. The aim of the article is to identify a model of nuclear-hydrogen synergy for use in NATO operations. We identify opportunities and threats related to mobile energy generation with nuclear-hydrogen synergy in NATO operations. The research presented in this paper identifies the best method of producing hydrogen using a nuclear microreactor. A popular and environmentally "clean" solution is electrolysis due to the simplicity of the process. However, this is less efficient than chemical processes based on, for example, the sulphur-iodine cycle. The results of the research presented in this paper show which of the methods and which cycle is the most attractive for the production of hydrogen with the use of mini-reactors. The verification criteria include: the efficiency of the process, its complexity and the residues generated as a result of the process (waste)—all taking into account usage for military purposes.

Chitosan-derived N-doped carbon materials are attractive candidates for the preparation of catalysts with a wide range of applications. Chitosan is a nitrogen rich (∼7 wt %) renewable biomass resource derived from seafood waste. Nitrogen-containing functional groups (amine and acetamide) of chitosan make it a suitable precursor for the synthesis of N-doped carbon materials. This perspective provides an overview on various techniques for the preparation and characterization of chitosan-based N-doped carbon materials and their application in the field of electrocatalysis and photocatalysis. Additional doping with nitrogen imparts greater electrochemical stability and basic character to the material due to the ability of nitrogen atoms to accept electrons. Nevertheless, each type of C–N bonding configuration has unique potential for catalytic reactions attributed to different electronic structure and catalytically active sites. The ability to acquire desired N-bonding states during the process of doping will provide a better control over the material application. The promising performance of chitosan-based N-doped carbon materials in electrocatalytic and photocatalytic reactions is attributed to their improved electronic structure and charge transfer properties. Moreover, research trends toward the design of chitosan-based N-doped carbons materials with required features for electrocatalytic and photocatalytic applications have also been identified. ; This publication is part of a project that has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant Agreement No. 711859 and from the financial resources for science in the years 2017-2021 awarded for the implementation of an international cofinanced project. Roger Gläser and Michael Goepel gratefully acknowledge support from the Leipzig Graduate School of Natural Sciences, Building with Molecules and Nano-objects, as well as from the Research Academy Leipzig.