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Hydrogen production from renewable sources is gaining increasing importance for application as fuel, in particular with high efficiency and low impact devices such as fuel cells. In addition, the possibility to produce more sustainable hydrogen for industrial application is also of interest for fundamental industrial processes, such as ammonia and methanol synthesis. Catalytic processes are used in most options for the production of hydrogen from renewable sources. Catalysts are directly involved in the main transformation, as in the case of reforming and of electro-/photo-catalytic water splitting, or in the upgrade and refining of the main reaction products, as in the case of tar reforming. In every case, for the main processes that reached a sufficiently mature development stage, attempts of process design, economic and environmental impact assessment are presented, on one hand to finalise the demonstration of the technology, on the other hand to highlight the challenges and bottlenecks. Selected examples are described, highlighting whenever possible the role of catalysis and the open issues, e.g. for the H2 production from reforming, aqueous phase reforming, biomass pyrolysis and gasification, photo- and electro-catalytic processes, enzymatic catalysis. The case history of hydrogen production from bioethanol for use in fuel cells is detailed from the point of view of process design and techno-economic validation. Examples of steady state or dynamic simulation of a centralised or distributed H2 production unit are presented to demonstrate the feasibility of this technology, that appears as one of the nearest to market. The economic feasibility seems demonstrated when producing hydrogen starting from diluted bioethanol. [ABSTRACT FROM AUTHOR]

The hydrolysis of silicon and its compounds to produce hydrogen for fuel cell remains a major problem. The main obstacle is the weak hydrolytic activity and slow kinetics of silicon. In this work, the alloying properties of Si and Ca to improve its hydrolytic activity, and studied the film breaking effect of different metals and halogen ions on its passivation layer. The results show that the hydrogen production of the alloy is still determined by its phase composition. Among the common metal (Ni, Bi, Sn) and halogen ions (F–, Cl–) catalyzed by hydrolysis, Ni and F– showed a good synergistic effect, resulting in a hydrogen yield of 269 mL/g at room temperature without alkali. The effects of metal ions and halogens on the hydrolytic properties of Ca–Si alloy were investigated, and Ni2+ and F— showed good synergistic effect. [ABSTRACT FROM AUTHOR]

Fuel cells are the most promising energy source for the future energy demand. The automobile industry is looking at the integration of fuel cells with electric vehicles (EV). This integration comes with many challenges like dynamic operational behaviors. For operating the fuel cell with maximum efficiency, this work proposes an Adaptive Neuro Fuzzy Inference System (ANFIS) based Maximum Power Point Tracking (MPPT) method. The hydrogen flow rate, pressure and stack temperature are the parameters considered to track the maximum power point of the fuel cell. The ANFIS-MPPT algorithm has been integrated with the 1.26 kW fuel cell in MATLAB/Simulink® and validated in different scenarios like dynamic variation in hydrogen pressure, stack temperature, load variation. The performance has been observed and compared with the conventional MPPT algorithms of Perturb and Observe (P&O) algorithm and Incremental Conductance (InC) algorithm. The proposed ANFIS-MPPT algorithm improves the power stability by 10–15% than the P&O and InC methods. Also, the proposed ANFIS-MPPT has 30% faster response as compared to the P&O algorithm, and 23% than the InC algorithm. From the analysis, it is observed that the ANFIS, P&O and InC methods are having the response time of 2.5 s, 3.6 s and 4.5 s respectively. Also the ANFIS method delivers the maximum power output of 1.26 kW, whereas the P&O and InC deliver 1.13 kW, 1.19 kW respectively. The detailed simulation analysis and results are presented in this paper. [ABSTRACT FROM AUTHOR]

One of the most critical components of a proton exchange membrane (PEM) fuel cell is the gas diffusion layer (GDL). Conventional preparation methods are complex, energy-consuming, and lack design flexibility. Additive manufacturing (AM) is widely used in various fields, with the fused deposition modeling (FDM) technique being the most widely used. With AM, GDLs can be designed and printed with precise control over their structure, porosity, and thickness. Previous research by the authors has shown high electrical resistance of the FDM-printed GDL. Thus, in this study, surface modification of printed GDL was performed to enhance its performance. The FDM-printed GDL with conductive graphite coating demonstrated a desirable breaking factor (2.11 kN/m) and air permeability (326 cm3/cm2/s). Its thickness, mass, and porosity were also determined to be appropriate and customizable. The performance of the manufactured GDL was examined in an open cathode air-breathing PEM fuel cell, indicating good feasibility at room temperature (20 °C). The results show that the application of the FDM technique in GDL manufacturing has great potential to revolutionize the fuel cell industry and drive progress toward a more sustainable future. [ABSTRACT FROM AUTHOR]

Power characteristics are important indicators of fuel cell performance. In the actual operation of fuel cells, changes in operating conditions lead to variations in their power characteristics. Therefore, it is imperative to explore the impact of operating conditions on power characteristics. This paper analyzes the factors influencing fuel cell power and uses sensitivity analysis to investigate how different factors affect fuel cell performance. The operating parameters are optimized using a Bayesian-optimized Gaussian process regression model. The research results indicate that temperature has the greatest impact on fuel cell power, followed by stoichiometry and backpressure. The Bayesian-optimized Gaussian process regression model performs the best, reducing its RSME from 0.1 to 0.0556. Residual analysis and regression characteristic analysis verify the optimized model's improved fitting and regression characteristics. Based on the Bayesian–Gaussian process regression model, the optimized operating parameters are obtained for maximum power: a temperature of 80 °C, stoichiometry of 4, and backpressure of 1.7 bar. This paper provides theoretical support for improving fuel cell performance. [ABSTRACT FROM AUTHOR]

Zn is a frequently used and sometimes even an inevitably involved element (when zeolitic imidazolate framework-8 (ZIF-8) is adopted as the precursor) for preparing high-performance Fe-N-C oxygen reduction reaction (ORR) catalysts. However, how the Zn element affects the physicochemical architecture of the catalysts, how it enhances the catalytic activity and whether Zn atoms serve as the active centers remain unclear. Herein, we proposed a novel route that adopted pyrrole as the precursor and flexibly controlled the addition of exogenous Zn and Fe dopants before pyrrole polymerization. In this way, a series of nitrogen-carbon catalysts with or without Zn or Fe doping were synthesized. The detailed characterization revealed the role of Zn and Fe doping in the catalyst morphology, pore structure, active site configurations, ORR catalytic activity and fuel cell performance. Importantly, the findings revealed that Zn doping has little effect on the ORR mechanism and pathway. It enhances ORR activity primarily by increasing the number of active sites via introducing more micro- and meso-pores, rather than by creating new active sites. While Fe doping participated in forming both pores and active site centers. Moreover, the catalyst that co-doped with Zn and Fe atoms (Zn-FeNC), synthesized via this simple and template-free route we proposed, presented a unique hollow and hierarchical pore structure with highly boosted ORR activity. It exhibited a 40 mV higher E1/2 value than Pt/C in alkaline media, along with a rapid current response in air-cathode of the direct formate fuel cell. These results are valuable in guiding the synthesis of high-performance Fe-N-C catalysts. [ABSTRACT FROM AUTHOR]

The importance of the oxygen reduction reaction (ORR) in fuel cells and zinc-air batteries is self-evident, and effective catalysts could significantly improve the catalytic efficiency of ORR. Single-atom catalysts are gaining increasing interest due to their high atom efficiency and effective catalytic performance compared to other catalyst types. While the optimal loading of catalytic sites in single-atom catalysts significantly influences their catalytic efficiency. However, creating stable single-atom catalysts with high-loading remains a difficult task. Therefore, we showcase and describe the latest developments in techniques for producing single-atom catalysts with high-loadings. In addition, the performance of noble metal, non-precious metal, and diatomic catalysts in ORR processes is summarized. What's more, the key difficulties and opportunities in the sector are demonstrated by examining the synthesis techniques and evaluating the performance and structure. This review will help researchers to advance the research process of high-loading single-atom catalysts and accelerate their practical application in the field of ORR research. [ABSTRACT FROM AUTHOR]

Proton-exchange-membrane fuel cells demand highly efficient catalysts for the oxygen reduction reaction, and core-shell structures are known for maximizing precious metal utilization. Here, we reported a controllable "carbon defect anchoring" strategy to prepare Pt1Ni1@Pt/C core-shell nanoparticles with an average size of ~2.6 nm on an in-situ transformed defective carbon support. The strong Pt–C interaction effectively inhibits nanoparticle migration or aggregation, even after undergoing stability tests over 70,000 potential cycles, resulting in only 1.6% degradation. The stable Pt1Ni1@Pt/C catalysts have high oxygen reduction reaction mass activity and specific activity that reach 1.424 ± 0.019 A/mgPt and 1.554 ± 0.027 mA/cmPt2 at 0.9 V, respectively, attributed to the optimal compressive strain. The experimental results are generally consistent with the theoretical predictions made by our comprehensive microkinetic model which incorporates essential kinetics and thermodynamics of oxygen reduction reaction. The consistent results obtained in our study provide compelling evidence for the high accuracy and reliability of our model. This work highlights the synergy between theory-guided catalyst design and appropriate synthetic methodologies to translate the theory into practice, offering valuable insights for future catalyst development. Efficient and stable catalysts for oxygen reduction reactions are difficult to achieve due to slow kinetics and degradation. Here, the authors use a 'carbon defect anchoring' strategy to create Pt1Ni1@Pt core-shell nanoparticles with high activity and durability. [ABSTRACT FROM AUTHOR]

The establishment of reactive oxygen species (ROS) elimination sites in iron-nitrogen-carbon (Fe-N-C) electrocatalysts to achieve durable proton-exchange membrane fuel cells (PEMFCs) performance has attracted broad interest. However, realizing ROS removal efficiency and oxygen reduction reaction (ORR) activity within a single system represents a significant challenge to date. Herein, we demonstrate uniform ROS elimination sites and ORR centers through an electrochemical reconstruction method on the parallel sites of Fe@CeNC electrocatalyst for durable PEMFC. During the reconstruction process, the Fe sites can retain their original configuration. Meanwhile, the pristine Ce clusters will evolve into more efficient, highly dispersed sites. Furthermore, the reconstructed Fe and Ce sites exhibit favorable energy barriers for the ORR and ROS elimination pathways, respectively, thereby maintaining ORR activity and achieving high ROS tolerance. Consequently, the PEMFC assembled with our catalyst shows only a 2% decay in power density after the accelerated durability test. We anticipate that this parallel structure design will provide new insight into the development of more durable electrocatalysts for PEMFCs. [ABSTRACT FROM AUTHOR]

Efficient catalysis of ammonia borane (AB) holds potential for realizing controlled energy release from hydrogen fuel and addressing cost challenges faced by hydrogen storage. Here, we report that amorphous domains on metallic Fe crystal structures (R-Fe2O3 Foam) can achieve AB catalytic performances and stability (turnover frequency (TOF) of 113.6 min−1, about 771 L H2 in 900 h, and 43.27 mL/(min·cm2) for 10×10 cm2 of Foam) that outperform reported benchmarks (most <14 L H2 in 45 h) by at least 20 times. These notable increases are enabled by the stable Fe crystal structure, while defects and unsaturated atoms in the amorphous domains form Fe-B intermediates that significantly lower the dissociation barriers of H2O and AB. Given that the catalyst lifetime is a key determinant for the practical use in fuel cells, our R-Fe2O3 Foam also provides decent H2 supply (180 mL H2/min, AB water solution of 7.5 wt% H2) in a driven commercial car fuel cell at stable power outputs (7.8 V and 1.6 A for at least 5 h). When considered with its facile synthesis method, these materials are potentially very promising for realizing durable high-performance AB catalysts and viable chemical storage in hydrogen powered vehicles. Hydrogen storage and release are critical issues for commercial use. Here, authors report a Fe Foam with amorphous domains for the hydrolysis of ammonia borane with ultra-long lifetime over 900 h, realizing the on-board H2 supply of a model car. [ABSTRACT FROM AUTHOR]

The durability of polymer electrolyte fuel cells (PEFCs) in fuel cell electric vehicles is important for the shift from passenger cars to heavy-duty vehicles. The components of a PEFC, namely the proton exchange membrane (PEM), catalyst layer (CL), and gas diffusion layer (GDL), contribute to the degradation of the fuel cell performance. In this paper, we propose a method for simultaneously evaluating the degradation rates of these components by combining electrochemical characterization with operando synchrotron X-ray radiography. The open-circuit voltage, electrochemically active surface area (ECSA), and water saturation were used as the degradation indicators for the PEMs, CLs, and GDLs, respectively. The results of two accelerated stress tests (loading and start-stop cycles) after 10,000 cycles showed that the increase in water saturation owing to the loss of hydrophobicity due to carbon corrosion in the cathode GDL occurred on the same timescale as the degradation in the PEM and cathode CL. Specifically, during the load cycle AST, the cathode CL degraded with a 26% reduction in the ECSA along with the cathode GDL degradation with a 10% increase in water saturation. This suggests that more efforts should be devoted to studies on the durability of GDLs for heavy-duty applications. [ABSTRACT FROM AUTHOR]

The design of the reactant gas flow field structure in bipolar plates significantly influences the performance of proton exchange membrane fuel cells (PEMFCs). In this study, we introduced four innovative U-shaped flow field designs, namely: In-Out Multi-U, Out-In Multi-U, Distro In-Out Multi-U, and Distro Out-In Multi-U. To investigate the impact of these various flow fields on PEMFC performance, we conducted computational fluid dynamics (CFD) numerical simulations, validated through model experiments. Our results indicate that the Distro Out-In Multi-U flow field offers notable advantages compared to the conventional parallel flow field (CPFF) and conventional serpentine flow field (CSFF). These benefits include reduced inlet and outlet pressures, lower liquid water content, more uniform liquid water distribution, and a more even current density distribution. Furthermore, the Distro Out-In Multi-U design demonstrates improved efficiency, consuming less H2 (91.9%) than the CSFF while achieving a higher net power density output (10.1%). As a result, for the same power output, the Distro Out-In Multi-U utilizes only 83.5% of the H2 consumed by the CSFF. In summary, the U-shaped structured flow field exhibits superior output performance, enhanced energy efficiency, and improved resistance to flooding. These findings suggest that the U-shaped flow field design holds significant potential as a reactive flow field for PEMFCs. [ABSTRACT FROM AUTHOR]

The paper proposes an instantaneous power theory (IPT) based an improved low voltage ride-through (LVRT) strategy for photovoltaic-proton exchange membrane fuel cell (PV-PEMFC) based grid following hybrid microgrid architecture. The concept of the instantaneous power theory-based proportional-integral control (IPT-PIC) mechanism has been introduced to enhance the dynamic response of the grid-tied power electronic medium. Based on the direct quantities measured, the processed IPT-PIC output has been used to regulate the active and reactive current injection during the grid side contingencies. Besides, the instantaneous power theory-based fuzzy current control (IPT-FCC) mechanism has also been proposed and compared with the conventional instantaneous power theory-based approaches and found to be suitable for real field applications, particularly in the hybrid microgrid architecture. The percentage improvement of the LVRT capability has been found in the detailed simulated platform using MATLAB/Simulink 2021a. Furthermore, the response time, computational burden and real-time applicability have been evaluated in the dSPACE DS1103PPC controller board. [ABSTRACT FROM AUTHOR]

Adapting the power and energy systems by integrating renewable sources is necessary to address climate change. On the other hand, microgrids are gaining prominence in meeting power and energy requirements, including in remote locations. Consequently, the power system's penetration of renewable energy-based microgrids is increasing. Planning an isolated microgrid necessitates cost-effective capacity sizing of energy sources and storage systems for maintaining continuity in power supply. Considering the variability and uncertainty of photovoltaic (PV), wind energies, and load variations, deciding the optimal size of renewable-rich, isolated microgrids is challenging. Batteries and fuel cells are potential storage solutions for managing variability. However, a more trustworthy sizing approach is necessary to maximize power availability at the lowest possible cost, even in the face of uncertainty. Moreover, providing the microgrid owner with the opportunity to choose from a range of optimal solutions is also essential. Therefore, incorporating the uncertainty handling feature with the help of robust assessment under worst-case scenarios in the multi-objective optimization method can provide a more trustworthy solution. In this connection, a novel algorithm is proposed that instills robustness in the solutions provided by traditional non-dominated sorting genetic algorithm-II (NSGA-II), which can offer multiple break-even solutions. The isolated microgrids with PV, wind as sources, and storage technologies such as Lithium-ion (Li-ion) batteries, fuel cells, and a combination of both, a less explored scenario, have been compared to determine the effective storage option over the long run while considering uncertainties in renewable energy and load variations. The NSGA-II benchmark solutions developed under these uncertainties and variations are used to validate the robustness of the solutions obtained from the proposed robust algorithm. With a good trade-off between the cost and availability aspects, the proposed algorithm is found to be superior in getting maximum availability with minimum cost under uncertainties. [ABSTRACT FROM AUTHOR]

The performance of a PEM fuel cell that uses hydrogen as the fuel and pure oxygen as the oxidant strongly depends on water management, which has been primarily studied in a single-channel domain. Therefore, there is a need to examine water distribution throughout the entire fuel cell domain, including both the anode and cathode sides. Liquid water can cause flooding in the gas diffusion layer, catalyst layer, and channels, reducing the active surface area of the catalyst and, consequently, the reaction rate. Phase transfer between liquid water and water vapor influences the buildup of liquid water in these domains. In the present work, a three-dimensional, non-isothermal, two-phase numerical model incorporating both the cathode and anode domains has been developed to study water distribution. This model includes water phase transition in the gas diffusion layer, catalyst layer, and channels. The mixed flow distributor is used to analyze water formation and distribution throughout the domain. The study shows that using pure oxygen at the inlet increases the ohmic region in the polarization curve and decreases concentration losses, which could be important for applications such as spacecraft. Additionally, the effects of liquid water accumulation in the porous layers on reactant transport and cell performance are investigated. [ABSTRACT FROM AUTHOR]

H2 recycling between naphthalene, tetralin and decalin can be a promising application in chemical hydrogen storage, which is an important area for hydrogen fuel cell applications. Pt-based catalysts can be used in the dehydrogenation reaction for this purpose and support modification can effectively improve the catalytic performance. Effects of preparation method, Mg/Al molar ratio and metal composition on the Pt-based LDH-derived nanoplatelets catalysts for decalin dehydrogenation were systematically investigated in this work. The results out of this study indicated that the preparation method, Mg/Al molar ratio and metal composition exert significant effects on the microstructure and catalytic performance of the catalysts for decalin dehydrogenation. The Pt/MgAl-LDO catalyst with a Mg/Al molar ratio of 4 prepared by hydrothermal method yielded the largest specific surface area of 374 m2/g and the smallest average Pt particle size of 1.62 nm, which exhibited excellent H2 production yield of 5.94 mol/gPt. These are mainly attributed to the sheet-like structure, large specific surface area and strong Pt-support interaction, leading to the superior Pt dispersion. This work provides a new approach for the preparation of low-cost and high-performance decalin dehydrogenation catalysts, which is of great significance for the application of liquid-phase organic hydride hydrogen storage technology. [ABSTRACT FROM AUTHOR]

This work demonstrates the application of urea-powered paper-based fuel cells (PFCs) with Hydrogen Peroxide (H2O2) as the oxidant to drive a flexible electronic circuit (ring oscillator (RO)), for the first time. Herein, the electrochemical performance of four different PFCs has been studied by employing non-precious electrodes as the anode and cathode. These are the membraneless PFC with (i) Toray carbon paper (CP) (ii) Nickel (Ni)-mesh (iii) Nickel Cobalt nanoparticles supported on reduced Graphene Oxide loaded on the CP (Ni Co@rGo@CP) and (iv) membrane-based PFC with Ni Co@rGo@CP as the electrodes. In each PFC the same electrode is employed on both the sides. A single membraneless-PFC with Ni-Co@rGo@CP as electrodes delivered a peak power density (Pmax) of 55 µW cm−2, maximum current density (Jmax) of 371 µA cm−2 and an open-circuit voltage (OCV) of 0.7 V at 3 M urea. While, a single membrane-based PFC assembled on an anion exchange membrane with Ni-Co@rGo@CP electrodes, delivered a Pmax of ≈70 µW cm−2 and Jmax of ≈500 µA cm−2 at an OCV of 0.7 V with 3 M urea. Subsequently, a stack of two membrane-based PFCs delivered an OCV of ≈1.4 V for 400 s. Finally, this stack is employed as a power source to drive a RO. The measured frequency and peak-to-peak voltage are 37.52 kHz and 1.04 V, respectively. This demonstration opens a window to implement self-contained flexible electronic system using PFCs as the power source with minimal e-waste. [ABSTRACT FROM AUTHOR]

This work presents simple post-treatment methods to selectively and partially remove the Pd core of Pd–Pt core–shell (Pt@Pd/C) catalysts. The proton exchange membrane fuel cell with the post-treated Pt@Pd/C cathode (Pt loading: 0.10 mg·cm−2) delivers an impressive peak power density of 1.2 W·cm−2. The partial removal of Pd core endows an ultrahigh oxygen reduction reaction (ORR) mass activity of 0.32 A·mgPGM−1 when normalized to the platinum group metal (PGM) mass, or equivalently 0.55 A·mgPt−1 at 0.9 V measured in a fuel cell. The post-treatment thickens the Pt shells and mitigates the Pd dissolution during potential cycling. As a result, the post-treated core–shell catalyst demonstrates superior durability in ORR mass activity and polarization power density retention than untreated core–shell catalyst and benchmark Pt/C. In-situ inductively coupled plasma-mass spectrometry (ICP-MS) results highlight that the amount of dissolved Pd in post-treated core–shell catalyst is 17-times lower than that of the untreated one. Our findings highlight the importance of structural tuning of catalysts in enhancing their mass activity and durability. [ABSTRACT FROM AUTHOR]

The microbial fuel cell (MFC) is considered a modern technology used for treating wastewater and recovering electrical energy. In this study, a new dual technology combining MFC and a specialized biofilter was used. The anodic materials in the system were crushed graphite, either without coating (UFB-MFC) or coated with nanomaterials (nano-UFB-MFC). This biofilter served as a barrier to retain and remove turbidity and suspended solids, while also facilitating the role of bacteria in the removal of organic pollutants, phosphates, nitrates, sulfates, oil and greases. The results demonstrated that both systems exhibited high efficiency in treating kitchen wastewater, specifically greywater and dishwashing wastewater with high detergent concentrations. The removal efficiencies of COD, oil and grease, suspended solids, turbidity, nitrates, sulfates, and phosphates in first UFB-MFC were found to be 88, 95, 89, 86, 87, 75, and 94%, respectively, and in Nano-UFB-MFC were 86, 99, 95, 91, 81, 88, and 95%, respectively, with a high efficiency in recovering bioenergy reaching a value of 1.8 and 1.5 A m−3, respectively. The results of this study demonstrate the potential for developing MFC and utilizing it as a domestic system to mitigate pollution risks before discharging wastewater into the sewer network. [ABSTRACT FROM AUTHOR]

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The serious problem of carbon monoxide (CO) poisoning on the surface of Pt-based catalysts has long constrained the commercialization of proton exchange membrane fuel cells (PEMFCs). Regeneration of Pt sites by maintaining CO scavenging ability through precise construction of the surface and interface structure of the catalyst is the key to obtaining high-performance CO-resistant catalysts. Here, we used molybdenum carbide (MoCx) as the support for Pt and introduced Ru single atoms (SA-Ru) at the Pt-MoCx interface to jointly decrease the CO adsorption strength on Pt. More importantly, the MoCx and SA-Ru are immune to CO poisoning, which continuously assists in the oxidation of adsorbed CO by generating oxygen species from water dissociation. These two effects combine to confer this anode catalyst (SA-Ru@Pt/MoCx) remarkable CO tolerance and the ability to operate stably in fuel cell with high CO concentration (power output 85.5 mW cm−2@20,000 ppm CO + H2 – O2), making it possible to directly use the cheap reformed hydrogen as the fuel for PEMFCs. Here, authors report a Pt-based catalyst resistant to high concentration CO poisoning for fuel cell applications, making it possible to use reformed hydrogen directly as fuel for fuel cells. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cell (PEMFC) parameter extraction is an important issue in modeling and control of renewable energies. The PEMFC problem's main objective is to estimate the optimal value of unknown parameters of the electrochemical model. The main objective function of the optimization problem is the sum of the square errors between the measured voltages and output voltages of the proposed electrochemical optimized model at various loading conditions. Natural rabbit survival strategies such as detour foraging and random hiding are influenced by Artificial rabbit optimization (ARO). Meanwhile, rabbit energy shrink is mimicked to control the smooth switching from detour foraging to random hiding. In this work, the ARO algorithm is proposed to find the parameters of PEMFC. The ARO performance is verified using experimental results obtained from conducting laboratory tests on the fuel cell test system (SCRIBNER 850e, LLC). The simulation results are assessed with four competitive algorithms: Grey Wolf Optimization Algorithm, Particle Swarm Optimizer, Salp Swarm Algorithm, and Sine Cosine Algorithm. The comparison aims to prove the superior performance of the proposed ARO compared with the other well-known competitive algorithms. [ABSTRACT FROM AUTHOR]

In this paper, a new method is designed to effectively determine the parameters of proton exchange membrane fuel cells (PEMFCs), i.e., ξ 1 , ξ 2 , ξ 3 , ξ 4 , R C , λ , and b . The fuel cells (FCs) involve multiple variable quantities with complex non-linear behaviours, demanding accurate modelling to ensure optimal operation. An accurate model of these FCs is essential to evaluate their performance accurately. Furthermore, the design of the FCs significantly impacts simulation studies, which are crucial for various technological applications. This study proposed an improved parameter estimation procedure for PEMFCs by using the GOOSE algorithm, which was inspired by the adaptive behaviours found in geese during their relaxing and foraging times. The orthogonal learning mechanism improves the performance of the original GOOSE algorithm. This FC model uses the root mean squared error as the objective function for optimizing the unknown parameters. In order to validate the proposed algorithm, a number of experiments using various datasets were conducted and compared the outcomes with different state-of-the-art algorithms. The outcomes indicate that the proposed GOOSE algorithm not only produced promising results but also exhibited superior performance in comparison to other similar algorithms. This approach demonstrates the ability of the GOOSE algorithm to simulate complex systems and enhances the robustness and adaptability of the simulation tool by integrating essential behaviours into the computational framework. The proposed strategy facilitates the development of more accurate and effective advancements in the utilization of FCs. [ABSTRACT FROM AUTHOR]

The solid oxide direct carbon fuel cell (SO–DCFC) is a vital future technology for producing high-efficiency and environmentally friendly electricity. To improve the performance of SO–DCFC, it is required to examine the optimal operation condition selection and anode reaction process optimization. The DCFC reaction model is derived from the anode Boudouard reaction in this study. Electrochemical reaction dynamics, mass transfer, and electrode processes are incorporated into the model. Higher Boudouard reaction rate, gasification rate, and power density of anode carbon were discovered to impact the performance of fuel cells directly. In addition, simulation provides the CO concentration and current density distribution under different output voltage settings, which can be used to assess the performance and give a basis for the best design of DCFC. [ABSTRACT FROM AUTHOR]

In practical applications, the proton exchange membrane (PEM) fuel cell stack is often exposed to wind environment, and the speed and direction of the ambient wind are random. The performance variation of an open-cathode PEM fuel cell under various ambient wind directions and speeds was studied. The results show that when the ambient wind direction is opposite to the cathode reactant or from the side of stack, the stack temperature increases and the stack power decreases finally. Moreover, with the increase in the wind speed, the running time of the stack is shortened significantly. For the ambient wind in the same direction as the cathode gas, the stack power increases at a high current and decreases at a low current. For the given speed and direction of ambient wind, the increased air flow rate of fan could alleviate the interference of ambient wind on the stack performance and temperature. However, while the stack temperature is more than the allowable maximum operating temperature, the stack power declines even though the air flow rate of fan increases. [ABSTRACT FROM AUTHOR]

Salt-doped block copolymers have widespread applications in batteries, fuel cells, semiconductors, and various industries, where their properties crucially depend on phase separation behavior. Traditionally, investigations into salt-doped diblock copolymers have predominantly focused on microphase separation, overlooking the segregation between ionic and polymeric species. This study employs weak segregation theory to explore the interplay between phase separation dominated by the polymer-modulated mode and the salt-out-modulated mode, corresponding to microscopic and macroscopic phase separations, respectively. By comparing diblock copolymers doped with salts to those doped with neutral solvents, we elucidate the significant role of charged species in modulating phase behavior. The phase separation mode exhibits a transition between the polymer-modulated and salt-out-modulated modes at different wavenumbers. In systems doped with neutral solvents, this transition is stepwise, while in salt-ion-doped systems, it is continuous. With a sufficiently large Flory-Huggins parameter between ions and polymers, the salt-out-modulated mode becomes dominant, promoting macrophase separation. Due to the solvation effect of salt ions, salt-doped systems are more inclined to undergo microphase separation. Furthermore, we explore factors influencing the critical wavenumber of phase separation, including doping level and the Flory-Huggins parameters between two blocks and between ions and polymeric species. Our findings reveal that in a neutral solvent environment, these factors alter only the boundary between micro- and macro-phase separations, leaving the critical wavenumber unchanged in microphase separation cases. However, in a salt-doped environment, the critical wavenumber of microphase separation varies with these parameters. This provides valuable insights into the pivotal role of electrostatics in the phase separation of salt-doped block copolymers. [ABSTRACT FROM AUTHOR]

The oxygen reduction reaction (ORR), occurred at cathodes in fuel cells, eco-friendly energy-conversion system, requires efficient electrocatalysts to overcome sluggish reaction kinetics. In this work, to enhance the ORR performance by decreasing potentials, we developed carbonized zeolite-imidazolate frameworks (ZIF) containing Co atoms (Co–C). The final product is produced by two-step process including (i) the formation of ZIF with Co species, and (ii) carbonization of the ZIF using high temperature treatment. Morphological characterizations revealed that the Co–C has polygon-shaped ZIF-based materials with metallic Co particles wrapped by layered carbon structures. The amount of Co atoms is found to be ~ 4 wt%, possessing a large surface area of 718 m2/g. X-ray photoelectron spectroscopy measurements further supported the formation of sp2 carbon structures with N-doping. The Co–C products exhibit an efficient electrocatalytic ORR performance in alkaline media, with their onset and half-wave potentials as of 0.97 and 0.86 V, comparable to those of Pt/C. Furthermore, Co–C shows the excellent cyclic durability and stability against for methanol poisoning. Collectively, this system including Co-based active species on ZIF networks provides a promise route for the development of efficient ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

This work reports a novel TiO2/g-C3N4 photoanode-based photocatalytic fuel cell (PFC) designed to convert chemical energy from simulated wastewater. The g-C3N4 modified TiO2 nanorod was successfully synthesized by a facile hydrothermal method. The results indicated that the maximum photocurrent density reached 2.44 mA cm-2 at 1.23 V vs. RHE by 1.167 g L-1 g-C3N4 loaded TiO2 composite. On the basis of analysis, the photoelectrochemical mechanism of the composite photoanode was proposed. This mainly demonstrated that the composite photoanode increases the electron donor density and boosts charge separation efficiency. In addition, the power density and hydrogen production of the proposed PFC were enhanced by 5.37 and 1.49 times compared to TiO2 photoanode-based PFC. To find the origins of the excellent performance of PFC, the influence of the organic compounds were investigated. The ESR measurement results indicated that the organic matter was captured by the photoexcited holes directly to facilitate the charge separation. The achieved power density and hydrogen production of 0.14 mW cm-2 and 21.60 μmol h-1 cm-2 were measured using RhB as the model pollutant, which was 2.42 and 1.23 times higher than the experiments with PBS electrolyte. This study proposed a novel PFC system converts the organic pollutant to the hydrogen and the electricity. [ABSTRACT FROM AUTHOR]

Carbon-supported platinum-lanthanum (Pt-Ln) intermetallic compound (IMC) nanoparticles with high activity and robust stability have been demonstrated as promising cathode catalysts for proton-exchange membrane fuel cells. However, the preparation of Pt-Ln IMC catalysts needs high-temperature annealing treatment that inevitably causes nanoparticle sintering, resulting in significant reduction of the electrochemical surface area and mass-based activity. Here, we prepare small-sized M-doped Pt5Ce (M = Ga, Cd, and Sb) IMCs catalysts via a low-melting-point metal doping strategy. We speculate that the doping of low-melting-point metals can facilitate the generation of vacancies in the crystal lattice through thermal activation and thus reduce the kinetic barriers for the formation of intermetallic Pt5Ce catalysts. The prepared Ga-doped Pt5Ce catalyst exhibits a higher electrochemical active surface area (81 m2·gPt−1) and a larger mass activity (0.45 A·mgPt−1 at 0.9 V) over the undoped Pt5Ce and commercial Pt/C catalysts. In the membrane electrode assembly test, the Ga-doped Pt5Ce cathode delivers a power density of 0.98 W·cm−2 at 0.67 V, along with a voltage loss of only 27 mV at 0.8 A·cm−2 at the end of accelerated stability test. [ABSTRACT FROM AUTHOR]

Optimization of Pt atom utilization efficiency is critical for the development of proton-exchange-membrane fuel cells. Here we aim to develop an efficient oxygen reduction reaction (ORR) catalyst with a low Pt content through the concurrent modification of Pt-Co alloy catalysts and carbon substrate. In the present study, ultrafine Pt-Co alloy nanoparticles are successfully synthesized and stabilized by topological carbon defects via adopting the ammonia thermal treatment. Despite the low Pt loading, the obtained catalyst exhibits an impressive half-wave potential of 0.926 V versus the reversible hydrogen electrode in 0.1 M HClO4 electrolyte. Furthermore, the durability testing using the timed-current method demonstrates a tiny loss of only 3.6% after 12 h. Both experimental results and theoretical calculations demonstrate that topological carbon defects significantly enhance the charge transfer processes at the alloy/carbon interface, contributing to the strong electronic metal-support interactions between the Pt-Co alloy nanoparticles and topological carbon defects. These interactions, along with the alloy effect, play a crucial role in promoting the ORR performance in acidic media. [ABSTRACT FROM AUTHOR]

In this study, three different Switched-Capacitor Enhanced boost quasi Z source (SCEq-Zs) DC–DC converters are presented, out of which the converter having a switched capacitor network positioned in series with the enhanced boost q-Zs network (SCEq-Zs-3) provides the common ground path and less output capacitor stress. This converter has a high voltage conversion ratio with low voltage stress on active and passive devices like capacitors, diodes, and the power semiconductor switch in comparison to other converters. This unidirectional hybrid switched-capacitor with a quasi Z source combination provides continuous and ripple-free source current mostly suitable for fuel cell applications. This leads to reduced voltage fluctuations at the input, providing a steady source of power to the converter. The converter is comprehensively analyzed and the operating principle along with waveforms is presented in this paper. A systematic comparison with other DC–DC boost converters is brought to view. A scaled-down 200V/200W prototype for the suggested converter is developed to verify the results of the theoretical study. A maximum efficiency of 95.85 % is measured. To demonstrate the effectiveness of the suggested converter, detailed experimental findings are presented. [ABSTRACT FROM AUTHOR]

Alloys of platinum with alkaline earth metals promise to be active and highly stable for fuel cell applications, yet their synthesis in nanoparticles remains a challenge due to their high negative reduction potentials. Herein, we report a strategy that overcomes this challenge by preparing platinum-magnesium (PtMg) alloy nanoparticles in the solution phase. The PtMg nanoparticles exhibit a distinctive structure with a structurally ordered intermetallic core and a Pt-rich shell. The PtMg/C as a cathode catalyst in a hydrogen-oxygen fuel cell exhibits a mass activity of 0.50 A mgPt−1 at 0.9 V with a marginal decrease to 0.48 A mgPt−1 after 30,000 cycles, exceeding the US Department of Energy 2025 beginning-of-life and end-of-life mass activity targets, respectively. Theoretical studies show that the activity stems from a combination of ligand and strain effects between the intermetallic core and the Pt-rich shell, while the stability originates from the high vacancy formation energy of Mg in the alloy. Fuel cells are promising for various applications but need durable electrocatalysts. Here, the authors present a solution-phase derived Pt-Mg alloy endowed with a Pt-rich shell and an intermetallic core, showing high durability and activity. [ABSTRACT FROM AUTHOR]

In diverse materials science spanning from fine ceramics to lithium-ion batteries and fuel cells, the particle–binder interactions in slurries play a crucial role in governing the ultimate performance. Despite numerous efforts to date, quantitatively elucidating these hidden interactions has remained a longstanding challenge. Here, we demonstrate a dynamic approach to evaluate adsorptive interactions between ceramic particles and polymeric binders entangled in a slurry utilizing differential centrifugal sedimentation (DCS). Particles settling under a centrifugal force field impart significant viscous resistance on the adsorbed binder, leading to its detachment, influenced by particle size and density. This behaviour directly reflects the particle–binder interactions, and detailed DCS spectrum analysis enables the quantitative assessment of nano-Newton-order adsorption forces. An important finding is the strong correlation of these forces with the mechanical properties of the moulded products. Our results provide insight that forming a flexible network structure with appropriate interactions is essential for desirable formability. [ABSTRACT FROM AUTHOR]

The constructed wetland coupled with a microbial fuel cell (CW-MFC) is a wastewater treatment process that combines contaminant removal with electricity production, making it an environmentally friendly option. This hybrid system primarily relies on anaerobic bioprocesses for wastewater treatment, although other processes such as aerobic bioprocesses, plant uptake, and chemical oxidation also contribute to the removal of organic matter and nutrients. CW-MFCs have been successfully used to treat various types of wastewater, including urban, pharmaceutical, paper and pulp industry, metal-contaminated, and swine wastewater. In CW-MFC, macrophytes such as rice plants, Spartina angalica, Canna indica, and Phragmites australis are used. The treatment process can achieve a chemical oxygen demand removal rate of between 80 and 100%. Initially, research focused on enhancing power generation from CW-MFC, but recent studies have shifted towards resource recovery from wastewater. This review paper provides an overview of the development of constructed wetland microbial fuel cell technology, from its early stages to its current applications. The paper also highlights research gaps and potential directions for future research. [ABSTRACT FROM AUTHOR]

The pollutant emissions of diesel-powered heavy-duty trucks (HDTs) seriously damage the air quality. The promotion of hydrogen fuel cell HDTs through purchase subsidy policy to reduce emissions has become an important approach to control air pollution. This study focuses on the impact of hydrogen fuel cell HDT purchase subsidies on air quality in the context of China, covering the panel data of 31 Chinese cities from 2014 to 2021 and applying a two-way fixed effects model to analyze the contribution of purchase subsidies and hydrogen refueling station construction subsidies to air quality. Results show that (1) the increase in purchase subsidies could improve the air quality by around 6.1% and there is a lag effect. (2) Purchase subsidies make a larger contribution to air quality compared with construction subsidies. (3) Purchase subsidies can improve air quality by reducing carbon emissions in transport industry. In sight of these results, policy makers should emphasize the implementation of purchase subsidies and hydrogen refueling station construction subsidies and stimulate manufacturers to improve the performance of hydrogen fuel cell so as to contribute more to the environment. [ABSTRACT FROM AUTHOR]

In the realm of renewable energy, platinum (Pt) nanoparticles are crucial components in fuel cells. They particularly excel in hydrogen fuel cells, where their role as catalysts significantly boosts the efficiency of electrochemical reactions. Cerium oxide nanoparticles are highly prized in engineering and industry for their exceptional catalytic abilities. They are particularly notable for their role in reducing vehicle emissions and facilitating the oxidation of carbon monoxide and hydrocarbons. Their oxygen storage capacity, crucial in regulating oxygen levels during catalytic reactions, is vital in automotive exhaust systems. Such an appealing area has led us to explore the dynamic behaviours of a specialized hybrid nanofluid- a mixture of radioactive platinum, cerium oxide, and water within a vertically extended vibrating Riga channel. This model is set under the cumulative consequences of sudden pressure gradient onset, electromagnetic forces, electromagnetic radiation, and chemical reactions. This physical model consists of a static right wall and a left wall that undergoes transverse vibrations. This flow scenario is mathematically described using time-dependent partial differential equations. A closed-form solution for the flow-regulating equations is obtained by harnessing the Laplace transform (LT) method. The study meticulously details the ascendancy of various critical parameters on the functions and quantities of the model, particularly for hybrid nanofluid (HNF) and nanofluid (NF), using graphical and tabular representations. Our findings manifest an expansion in the modified Hartmann number notably boosts the fluid velocity across the Riga channel. The fluid temperature in HNF is consistently lower in HNF compared to NF. The species concentration levels in HNF and NF lower with rising Schmidt numbers and chemical reaction parameters. A widened width of magnets and electrodes results in lowered shear stresses at the Riga wall in both HNF and NF. Furthermore, the rate of heat transfer (RHT) at the vibrating wall for HNF consistently shows higher values than for NF. These novel insights have far-reaching implications in various industrial and engineering applications, including the development of catalytic converters, the optimization of hydrogen fuel cells, the efficient oxidation of carbon monoxide and hydrocarbons, and advancements in materials processing techniques. [ABSTRACT FROM AUTHOR]

Recent research has focused on applying PEM fuel cell systems to heavy-duty unmanned aerial vehicles (UAVs) as eco-friendly power sources to enhance their mission capabilities. High-altitude operation poses challenges owing to low temperatures, poor oxygen concentrations, and humidity, which affect fuel cell performance. In this study, the thermal stability of a PEM fuel cell system for UAVs was analyzed using an integrated system model in MATLAB/Simulink. Parametric studies were conducted to analyze the thermal parameters of the stack and observe the changes in the cooling load of the system according to the cruising altitude, as well as variations in the optimal operating conditions to ensure the durability of the fuel cell stack. The results of this study are expected to contribute to the selection of optimal operating conditions and the development of thermal management strategies for PEM fuel cell-based UAVs operating at different cruising altitudes. [ABSTRACT FROM AUTHOR]

The proton exchange membrane fuel cell (PEMFC) in a fuel cell electric bus (FCEB) converts hydrogen's chemical energy into electrical energy. The fuel cell system comprises a fuel cell stack and a balance of plant (BOP) system, which efficiently controls the stack. Fuel cell and battery are sensitive to operational temperature, which directly impacts performance, lifespan, and safety. Therefore, a thermal management system (TMS) is necessary to maintain an appropriate temperature by dissipating the heat generated by the fuel cell and battery. In this study, the exponential or quadratic relationships between the power consumption of the major components of an FCEB and various factors, such as temperature and flow rate influencing the operational behavior and control of the components, were analyzed based on the results of a dynamometer vehicle test. Additionally, the vehicle's energy flow was calculated under different fuel cell load conditions. When the fuel cell operated at 56.3 kW, TMS power was 6.6 times higher than at 20 kW. At full load, under 90 kW, it increased to 17.4 times higher. The rise in fuel cell load correlated with higher heat generation, resulting in a significant increase in power consumption for both the radiator fan and coolant pump. [ABSTRACT FROM AUTHOR]

The global hydrogen demand is projected to increase from 70 million tons in 2019 to more than 200 million tons in 2030. Methane decomposition is a promising reaction for H2 production, coupled with the synthesis of valuable carbon nanomaterials applicable in fuel cell technology, transportation fuels, and chemical synthesis. Here, we review catalytic methane decomposition, with focus on catalyst development, deactivation, reactivation, regeneration, and on economics. Catalysts include mono-, bi-, and trimetallic compounds and carbon-based compounds. Catalyst deactivation is induced by coke deposition. Despite remarkable strides in research, industrialization remains at an early stage. [ABSTRACT FROM AUTHOR]

This paper presents the design of a 35 kW isolated fuel-cell DC–DC converter (FDC) with a hybrid switch structure. By utilizing a circuit structure and pulse-width modulation (PWM) method that enables the use of insulated-gate bipolar transistors (IGBTs), the price is reduced without a significant efficiency degradation even at frequencies of tens of kHz when compared to using all silicon carbide metal–oxide–semiconductor field-effect transistors (SiC-MOSFETs). The proposed converter is based on a PWM resonant converter, which has good switching characteristics and low-voltage stresses on the switching devices. However, it suffers from high cost owing to heavy current stresses. This problem can be solved using a hybrid switch structure that adopts IGBTs in the leading-leg switches. Considering the wide variations in the input and output voltages, the design of the main parameters, the selection of power semiconductors considering the switching characteristics, and the frequency selection method are presented. The feasibility of the proposed FDC design is verified using a prototype implemented with an output power of 35 kW (input voltage = 330–610 V and output voltage = 450–850 V) and a switching frequency of 40 kHz. [ABSTRACT FROM AUTHOR]

The fuel cell stack power mismatch problem limits the large-scale application of fuel cells. In order to guarantee the normal operation of the series fuel cell bank under fault condition, this paper proposes a multi-port DC converter for fuel cell distributed maximum power tracking based on the coupled inductor principle. The converter is based on the voltage equalization method and consists of a series fuel cell bank with a diode clamping circuit and a Boost converter in sequential cascade. In contrast to the degraded usage method of fuel cell stacks under fault conditions, the voltage equalization strategy does not affect the lifetime of non-faulty fuel cell units, so the overall system is more efficient. The proposed converter combines high output voltage gain and cell voltage equalization due to the use of only one switching tube. Simulation models are used to verify the feasibility and advancement of the proposed converter. [ABSTRACT FROM AUTHOR]

In order to investigate how uncertainty affects microgrid operation, a fundamental stochastic structure is provided in this research. The proposed random structure simulates load uncertainty errors, market pricing, and the manufacture of wind turbines and solar cells. There are two primary stages to the random structure that is suggested. Using the roulette wheel method and each random variable's probability density function, many scenarios are created in the first phase. Then the most likely scenarios are selected using the scenario reduction process. Using the above method, the random problem becomes several definite problems with different possibilities. In the second phase, any of the specific issues generated in the first phase may be solved with the novel and effective adaptive particle swarm optimization (APSO) technique. A microgrid with various sources, including a wind turbine, solar cell, microturbine, fuel cell, and energy storage device, is taken into consideration in order to assess the effectiveness of the suggested algorithm. The outcomes of the APSO algorithm are then compared with those of other algorithms. [ABSTRACT FROM AUTHOR]

The large-scale multi-attribute group decision-making (LSMAGDM) problem has become a hot research topic in the field of decision science. An R-numbers large-scale multi-attribute group decision-making (R-LSMAGDM) model is proposed to be constructed in this paper based on the advantages of R-numbers in capturing risks. First, the most commonly used clustering method, k-means, is introduced to determine the sub-groups. Then, a new sub-group weighting determination model is constructed by considering sub-group size and sub-group entropy. Next, we also build an optimized consensus-reaching model by improving the calculation method of the mean value. Then, the R-numbers weighted Hamy mean (RNWHM) operator is proposed to aggregate the sub-group information. In addition, the logarithmic percentage change-driven objective weighting (LOPCOW) method and the compromise ranking of alternatives from distance to ideal solution (CRADIS) method are used for attribute weighting calculation and alternative ranking, respectively. Finally, the effectiveness of the model is verified by an application example of hydrogen fuel cell logistics path selection. [ABSTRACT FROM AUTHOR]

This study focuses on developing an alternative membrane for PEMFC due to the disadvantages of using Nafion. Fluoroboric acid (FBA) was used as an additive material to SPEEK-PVA blend membranes at different weight ratios (1%, 5%, 7.5%, 10%, and 12.5%), and a synthesis procedure was carried out with the solution-casting. Thermal crosslinking was performed with all membranes. Utilizing FBA, with its highly electronegative fluorine groups, is a novel approach expected to enhance proton conductivity. The structural, morphological, and thermal properties of the synthesized membranes were determined by FTIR, XRD, SEM, TGA-DTG, and DSC. Water uptake capacity (WUC), swelling property, area change, dynamic mechanical analysis, ion exchange capacity (IEC), AC impedance analysis, hydrolytic stability, and oxidative stability analyses were performed for fuel cell applications. Although FBA does not have a crystal structure, the synergy it created with the SPEEK-PVA membrane increased the crystallinity of the membrane and, accordingly, glass transition temperature. SEM images of membranes at a ratio above 7.5% show that agglomerations occur in the structure and this is supported by other analyses. It was determined that the membrane composition with the highest WUC (16.44%), IEC (1.55 meq/g), and proton conductivity (0.57 S/cm) values contained 7.5% FBA from the characterization studies, and a single-cell performance test was actualized with this. 418 mA/cm2 current density and 250.8 mW/cm2 power density were obtained at 0.6 V cell potential, with the membrane containing 7.5% FBA. This study shows that the synthesized membrane, especially the FBA, is a promising option for PEMFC application. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) is a viable alternative to the finite fossil fuels to meet the escalating energy demands. Water splitting is a cleaner way of producing H2, which can effectively generate electricity via fuel cells. The slower oxygen evolution reaction (OER) with large overpotential hinders the practicality of the electrocatalytic water-splitting process to generate H2. Cobalt titanate (CoTiO3) and graphitic carbon nitride (g-C3N4) are promising candidates for OER catalysts. The composite of CoTiO3 supported on phosphorous doped g-C3N4 substrate (CoTiO3/P-C3N4) has been synthesized and demonstrated as an excellent electrocatalyst with enhanced charge transport properties exhibiting a lower overpotential of 310.0 mV, a lower charge transfer resistance (Rct) and faster OER kinetics. The synergistic interaction of CoTiO3 and P-C3N4 at the hetero-interface has resulted in enhancing the conductivity and the accessible active sites. The composite also exhibited appreciable operational stability and Faradaic efficiency. CoTiO3/P-C3N4 was thus proved to be competent to substitute the unstable and expensive benchmark catalysts in terms of cost, activity, and stability. [ABSTRACT FROM AUTHOR]

A Hydrogen fuel cell (HFC) broad range associated with Internet of Things (IoT) technologies that require slightly less and constant electricity made possible by remote climate monitoring connections. Novelty demonstrates a miniature HFC based on carbon cloth electrodes and sealing elements manufactured via 3D printing. Cobalt (II) Oxide (Co3O4)—reduced Graphene Oxide (rGO) and Platinum (Pt) based nanoparticles are coated over carbon cloth to increase the catalytic activity at the anode and cathode. Hydrogen is produced by using an aluminium foil (Al) that is stored in between the filter paper and through capillary action the sodium hydroxide pellets (NaOH) are applied and reacted with Al foil to produce hydrogen. The single HFC device working surface area of 1 × 1 cm2 effectively generates an open circuit voltage (OCV) of 1.3 V, a current density of 1.602 mA/cm2, and a peak power density of 761 mW/cm2. The fuel cell stability performance is monitored for up to 10 h. The power obtained from the HFC is stored in a supercapacitor and used to supply energy to the IoT component. The module includes a built-in sensor that monitors the temperature, pressure, and humidity. The measured data is then transmitted to a smartphone via Bluetooth. [ABSTRACT FROM AUTHOR]

This paper propose a wide gain single-bridge interleaved three-level LLC resonant converter with current sharing capability. This novel converter offers numerous advantages, including low cost, low current ripple, reduced voltage and current stress, widely gain range, high efficiency, good current sharing capability and versatile application scalability. Utilizing the three-level inverter + full-wave rectifier LLC converter as a representative case, the paper conducts an in-depth analysis and research on the proposed method. Finality, a 600 W experimental prototype was constructed and tested. Experimental results reveal that the proposed converter exhibits lower current ripple and a broader gain range. Moreover, the converter shows good current sharing capability (with a resonant element tolerance of 10%, the current error between the two phases does not exceed 12%) and high efficiency (peaking at 95.8%). [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) are compatible with perfluorosulfonic acid (PFSA) polymers due to their rich hydrophilic functional groups and nanoscale particle size, making them suitable as inorganic fillers for proton exchange membranes. In this work, CQDs synthesized by a simple microwave-assisted pyrolysis method were used to improve the performance of PFSA proton exchange membranes. Research indicates that at 80 °C and 100% relative humidity (RH), the proton conductivity of the PFSA membrane increased to 254 mS/cm with the addition of 0.5 wt% CQDs filler, compared to 249 mS/cm for the original PFSA membrane. This enhancement in proton conductivity is likely attributed to the hydrophilic functional groups present on CQDs, such as carboxyl groups (–COOH) and amino groups (–NH2). Furthermore, a notable decrease in hydrogen permeability was observed in the composite membranes due to the incorporation of CQDs. Specifically, the hydrogen permeability of the PFSA/CQDs-2 composite membrane was reduced by approximately 44% compared to the original PFSA membrane. This reduction in hydrogen permeability is likely a result of cross-linking between the sulfonic acid groups in PFSA and the amino groups in CQDs. In conclusion, CQDs contribute to better proton conductivity, lower hydrogen permeability, and enhanced thermal and mechanical stability for PFSA membranes, making them a potential membrane material for high-temperature operation in proton exchange membrane fuel cells. [ABSTRACT FROM AUTHOR]

Fuel cell vehicles (FCVs) are gaining significance due to their potential to reduce greenhouse gas emissions and dependence on fossil fuels. Their efficient fuel cell cycle makes them ideal for last-mile transportation, offering zero emissions and longer range compared to battery electric vehicles. Additionally, the generation of electricity through fuel cell stacks is becoming increasingly popular, providing a clean energy source for various applications. This paper focuses on utilizing the energy from fuel cycle bicycles when it's not in use and feeding it into the home DC grid. To achieve this, a dual-phase DC to DC converter is proposed to boost stack voltage and integrate with the 24 V DC home grid system. The converter design is simulated using the PSIM platform and tested in a hardware-in-the-loop (HIL) environment with real-time simulation capabilities. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) not only provide rapid dynamic response but also operate at low temperatures, which are desirable characteristics for transportation applications. However, metal bipolar plates in PEMFCs often deform under excessive clamping pressure, resulting in uneven pressure distribution. Rib-stiffened channels have been proposed to increase the structural stiffness of the bipolar plates, promoting durability. Parametric studies reveal that the supporting walls formed by the rib structure and a reduced top surface area contribute to better resistance against clamping force. Structural analysis and experimental assessments have confirmed the effectiveness of rib-stiffened channels in mitigating deformation. To ensure uniform compression of the gas diffusion layer during bolt assembly, a combined straight and rib-stiffened flow field has been designed and validated through structural simulations. Rib structures do not compromise fuel cell performance, as proved by computational fluid dynamics simulation with electrochemical reaction. [ABSTRACT FROM AUTHOR]