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The increasing emission of carbon dioxide worldwide has emerged as a major global concern in the context of addressing climate change. Converting CO2 to high-value carbon materials is a promising solution to capture emitted carbon for achieving carbon neutrality. Furthermore, such conversion can provide carbon nanomaterials for key industries, including the lithium battery and fuel cell industries. Here, it is shown that sub-50 nm tangled carbon nanotubes (CNTs) can be synthesized by adjusting the metaborate concentration and the current density through the electrochemical conversion of carbon dioxide in a molten carbonate salt. The metaborate ion concentration affects the product selectivity and carbon morphology, and the current density is strongly related to the particle size of in situ seed catalysts supplied by the dissolution of an Ni-Fe-Cr alloy anode. The optimized process conditions control the nucleation and growth of carbon via a tip-growth mechanism, thereby promoting the formation of sub-50 nm CNTs rather than bulky irregular carbon particles. The Raman and Brunauer–Emmett–Teller analyses showed that the properties of the prepared CNTs depended on the synthetic parameters. This study provides deep insights into the mechanism underlying carbon synthesis through the electrochemical reduction of a molten carbonate salt. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) offer significant potential for conversion from chemical energy to electrical energy due to their significant low-temperature range, high power density, mobility, and increasing start-up. PEMFC design and applications have been simplified through the utilization of artificial neural network (ANN) based multi-objective optimization (ANN-MOO). This approach can be easily adjusted to consider multiple factors simultaneously, even when dealing with customized objective functions or new case scenarios. This study thoroughly examines the existing body of literature on the application of Artificial Neural Network-Multi-Objective Optimization in the Proton Exchange Membrane Fuel Cell industry. The original elucidation of ANN-MOO provided a full explanation of its definition, classifications, and structure. The study evaluates objectives, intelligence algorithms, and tradeoff methods in PEMFC, focusing on ANN-MOO's application in components, kinetics, control, performance, and hybrid systems. The relevant issues, including the techniques, variables, objectives, and outcomes of optimization, were enumerated and discussed. The present review aimed to examine the existing limitations in the field of study and put up suggestions for future research. [ABSTRACT FROM AUTHOR]

Azo-Schiff bases contain an azo photochrome showing isomerization accompanying with color change, and an imine moiety (which can contribute to the metal complexation capability). The syntheses of these molecules will be described, and their dyes applications will be discussed, such as for fuel cells, as photometric or colorimetric sensors. In addition, liquid crystals and their antibacterial efficiencies will also be discussed. [ABSTRACT FROM AUTHOR]

Due to the needs of industries for clean and environmentally friendly fuels today, new energy sources such as fuel cells are at the center of attention. Polymer fuel cells, meanwhile, require a short start-up time due to low operating temperature, high power density, no emission and very low noise, making them the best option for vehicles as an alternative to internal combustion engines. One of the most important reasons for fuel cell loss is the uneven distribution of reactants on the active area, which causes non-uniform reactions. Therefore, the use of an optimal flow field to improve the durability and performance of PEM fuel cells seems necessary. Although different studies introduced novel designs, a study comparing different patterns comprehensively to introduce the best ones is not performed yet. In this study, first, a numerical validation was performed with an experimental test that showed good accuracy. Then, to achieve efficient patterns, several flow field designs were inspired by previous effective designs and others were selected as superior designs from the literature. The effects of presented geometries on the performance of a PEMFC were investigated to improve its performance. In addition, efficient evaluation criteria from the literature were employed to better analyze the performance of such systems, and the ones consistent with the I-V performance were introduced. By surveying the criteria, a novel performance factor was introduced that showed the best agreement with the I-V performance. The results were obtained in single-phase and two-phase approaches, which lead to remarkable findings. The two-phase study revealed that the waved serpentine case has the highest electrical performance with the highest mass fraction of oxygen. [ABSTRACT FROM AUTHOR]

Converting hydrocarbons and greenhouse gases (i.e., carbon dioxide, CO2) directly into electricity through fuel cells at intermediate temperatures (450 to 550 °C) remains a significant challenge, primarily due to the sluggish activation of C–H and C=O bonds. Here, we demonstrated a unique strategy to address this issue, in which light illumination was introduced into the thermal catalytic CO2 reforming of ethane in the anode as a unique thermo-photo anode process for carbonate-superstructured solid fuel cells. The light-enhanced fuel activation led to excellent cell performance with a record-high peak power density of 168 mW cm−2 at an intermediate temperature of 550 °C. Furthermore, no degradation was observed during ~50 h operation. Such a successful integration of photo energy into the fuel cell system provides a new direction for the development of efficient fuel cells. [ABSTRACT FROM AUTHOR]

Against the backdrop of "carbon peak and carbon neutrality," the hydrogen and fuel cell vehicle industry are rapidly developing. Within the on-board hydrogen supply system, the hydrogen circulation pump serves as an essential component of the hydrogen fuel cell system. The spiral disk, as a core part of the hydrogen fuel cell system's vortex hydrogen circulation pump (VHCP), plays a crucial role in determining the performance of the hydrogen circulation system in hydrogen fuel cell vehicles. To meet the requirements for high-performance and high-reliability development of the hydrogen circulation pump, the VHCP scheme is adopted as the choice for the hydrogen pump solution. Through the magnetic suspension and no connection shaft structural design, the feasibility of applying the high speed and high flow hydrogen turbine was initially validated. Utilizing Fluent analysis software and high precision performance test bench, a comprehensive three-dimensional numerical simulation of the turbine design under various operating conditions was conducted and performance test verification, demonstrating that the performance meets the required specifications. By conducting research in both strength optimization design and performance requirement, two major technical challenges in turbine pump application were overcome. Combined with the experimental results of the turbine medium, it is concluded that the vortex pump can meet the flow and pressure rise under the premise of low power consumption in the hydrogen circulation system so as to perfectly increase the hydrogen return amount. Based on these findings, recommendations are proposed for the future development direction of hydrogen supply systems in hydrogen fuel cell vehicles. [ABSTRACT FROM AUTHOR]

Polyoxometalates (POMs) are three-dimensional materials with unique, exceptional physical and chemical characteristics. The performance of POM-derived materials is anticipated to be enhanced by the combination of POM and metal–organic frameworks (MOFs) due to the high surface areas of MOF materials. In this study, three kinds of T-POMs@ZIF-67 (T-PMo@ZIF-67, T-SiW@ZIF-67, and T-PW@ZIF-67) were prepared by doping a cobalt-based MOF (ZIF-67) with three POMs (phosphomolybdic acid, silicotungstic acid, and phosphotungstic acid). The results show that the power density of the T-PMo@ZIF-67 catalyst anode is 3.08 times that of the blank control anode and 1.34 times that of the CoMoO4 catalyst. These findings suggest that the synthesis of MOF derivatives by doping MOFs with POM will have significant potential for use in the fuel cell industry. [ABSTRACT FROM AUTHOR]

Wherever you go, everyone is talking about the skills gap - and the energy sector is no exception, especially when it comes to the field of hydrogen. While there is already an established education and training system in place for other areas of industry, things are only just getting started in the hydrogen and fuel cells industry. Since no market exists yet for electrolyzers or fuel cell applications, technical staff first need to be trained how to build these products as well as how to install, maintain and repair them. However, this requires appropriate education pathways and expert teachers who are able to pass on their knowledge to up-and-coming technicians. The good news is that many educational establishments have set about addressing this important issue in recent months. As a result, hydrogen academies and fuel cell seminars are springing up right across Germany. [ABSTRACT FROM AUTHOR]

Proton-Exchange Membrane Fuel Cells have emerged as a game-changer in the automotive sector due to their operational efficiency and eco-friendly nature. The impact of NAFION and the Proton-Exchange Membrane Fuel [...]

The article focuses on the fuel cell industry's performance in 2022, with insights into regional shipments, application analysis, and trends by fuel cell type. Topics include the dominance of Asia in fuel cell shipments, the slow growth of the industry despite increasing interest in hydrogen, and the need for sustained government support to drive the energy transition.

The present day energy supply scenario is unsustainable and the transition towards a more environmentally friendly energy supply system of the future is inevitable. Hydrogen is a potential fuel that is capable of assisting with this transition. Certain technological advancements and design challenges associated with hydrogen generation and fuel cell technologies are discussed in this review. The commercialization of hydrogen-based technologies is closely associated with the development of the fuel cell industry. The evolution of fuel cell electric vehicles and fuel cell-based stationary power generation products in the market are discussed. Furthermore, the opportunities and threats associated with the market diffusion of these products, certain policy implications, and roadmaps of major economies associated with this hydrogen transition are discussed in this review. [ABSTRACT FROM AUTHOR]

Fuel cells, as key carriers for hydrogen energy development and utilization, provide a vital opportunity to achieve zero-emission energy use and have thus attracted considerable attention from fundamental research to industrial application levels. Considering the current status of fuel cell technology and the industry, this paper presents a systematic elaboration of progress and development trends in fuel cell core components and key materials, such as stacks, bipolar plates, membrane electrodes, proton exchange membranes, catalysts, gas diffusion layers, air compressors, and hydrogen circulation systems. In addition, some proposals for the development of fuel cell vehicles in China are presented, based on the analysis of current supporting policies, standards, and regulations, along with manufacturing costs in China. The fuel cell industry of China is still in the budding stage of development and thus suffers some challenges, such as lagging fundamental systems, imperfect standards and regulations, high product costs, and uncertain technical safety and stability levels. Therefore, to accelerate the development of the hydrogen energy and fuel cell vehicle industry, it is an urgent need to establish a complete supporting policy system, accelerate technical breakthroughs, transformations, and applications of key materials and core components, and reduce the cost of hydrogen use. [ABSTRACT FROM AUTHOR]

As the use of both clean energy technologies and alternative fuels in the maritime sector is spreading, studies dealing with the installation of multi-MW power generation plants on board ships have been increasing. Considering this, the present work proposes a 12 MW Solid Oxide Fuel Cell (SOFC) to be installed on board a cruise ship of about 175000 gross tonnes, 345 m length, and powered by Liquefied Natural Gas (LNG). It is supposed that the SOFC generates electrical energy and provides part of the thermal power demand by integrating a heat recovery system. A zero-dimensional (0D) Aspen Plus model has been developed to optimize the onboard layout and to predict the performance of the integrated power plant. Specific parameters, such as the fuel utilisation factor, the pre-heated air temperature, the anodic recycle flow rate, and the exhaust gas temperature, have been manipulated to evaluate the overall efficiency of the integrated power plant under different operating conditions. The model has been validated by comparing the results obtained with data from literature and commercial SOFC modules. A layout configuration of the SOFC plant is suggested and the performances are investigated by varying the efficiency in the range of 60-40%. [ABSTRACT FROM AUTHOR]

In this work, a preliminary risk evaluation of the methanol/water storage in fuel cell integrated systems is performed. The system which couples methanol steam reforming and the fuel cell to generate electricity is considered as a solution in several industrial projects for onboard applications. The challenge of such a system is to control the thermal loads to operate under fully autothermal conditions, recycling the dissipated heat from the fuel cell to preheat and evaporate the reactant mixture. To implement these systems, safety issues must be identified and minimized. Considering the autothermal operating conditions of the methanol steam reforming unit, the water/methanol ratio was set at 3. Under these conditions, the mixture is safer than pure methanol in terms of flammability and toxicity, but not yet inherently safe. Starting from the generation of a hole on the storage tank as initiating event, the consequence analysis as well as some preliminary risk considerations is performed by using empirical models. In this work, the focus was on the effects of a vapour cloud explosion and comparisons were made between a methanol-water solution, pure methanol, and gasoline, used in the conventional internal combustion engine. [ABSTRACT FROM AUTHOR]

In the field of risk analysis regarding major accidents, the most commonly adopted techniques of analysis and evaluation are HazOp and Fault Tree Analysis (FTA), which have many application software and available established procedures to support risk analysts. Albatros III, developed on the basis of the experience gained with the previous software (Antonello et al. 2009, ref. [1]), aims to minimize wasted time by processing Fault Trees and Minimal Cut Sets (MCS) on the basis of the Hazop application. Basing the construction of the fault tree on the Hazop analysis also allows a more accurate and complete evaluation of the results. Fault trees are automatically obtained in graphical form and quantified. The MCS are also processed and displayed both by breaking down into categories associated with the different types of instrumentation, and by indicating the equations that compose them, with the level and incidence of the individual items. In this way it is also easy to obtain the SIL.A database containing reliability datasets is linked to the AlbatrosIII software, allowing the choice of individual data for the automatic calculation of the expected failure frequency or PFD of the system. [ABSTRACT FROM AUTHOR]

Hydrogen is one of the most promising power sources for meeting the aviation sector's long-term decarbonization goals. Although on-board hydrogen systems, namely, fuel cells, are extensively researched, the maintenance, repair and overhaul (MRO) perspective remains mostly unaddressed. This paper analyzes fuel cells from an MRO standpoint, based on a literature review and comparison with the automotive sector. It also examines how well the business models and key resources of MRO providers are currently suited to provide future MRO services. It is shown that fuel cells require extensive MRO activities and that these are needed to meet the aviation sector's requirements for price, safety and, especially, durability. To some extent, experience from the automotive sector can be built upon, particularly with respect to facility requirements and qualification of personnel. Yet, MRO providers' existing resources only partially allow them to provide these services. MRO providers' underlying business models must adapt to the implementation of fuel cells in the aviation sector. MRO providers and services should, therefore, be considered and act as enablers for the introduction of fuel cells in the aviation industry. [ABSTRACT FROM AUTHOR]