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Please wait a minute... For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails Select Parameters Affecting the Fuel Cell Reactions on Platinum Bimetallic Nanostructures Nicolas Alonso-Vante Electrochemical Energy Reviews    2023, 6 (1): 3-.   DOI: 10.1007/s41918-022-00145-7 Abstract （1583）      PDF       Knowledge map    Save In this paper the electrochemical properties of some platinum-based nanoalloys are reviewed. The revision is centered on electrocatalytic materials generated via the carbonyl chemical route (CCR). In considering the effects of segregation in these bimetals, the reaction of the hydrogen oxidation (HOR) and oxygen reduction (ORR) in the alkaline medium was investigated. The reaction kinetics of these electrochemical processes in the alkaline electrolyte is still a challenge. For the design of high-performance platinum-based electrocatalysts, it is of importance to know that the kinetics of HOR and ORR also depends on the Pt adsorbate. The electrochemical analysis, based on the study of Pt nanoalloyed surfaces with different Pt-adsorbate interactions, was taken into account. A clear trend in the HOR as well as the ORR activity, in the alkaline electrolyte, was established, revealing that the activity changes in the order PtSn/C < PtCr/C < Pt/C (JM) < PtCo/C < PtNi/C for the former, and for the latter Pt/C (Tek) < Pt/C (JM) < PtCr/C < PtNi/C. The decisive effect of the Pt-Had energy on the HOR kinetics on Pt surfaces apparently depends on the oxophilicity role of the metal to favor M-OHad. The apparent electronic effect is not evident on these materials, except if a strong metal interaction is induced per se with either the carbon or oxide supports, e.g., the Pt/SnO2-C interface in acidic media. Favorable effects of Pt-Had energy on HOR kinetics were found with the oxophilicity of the sp2 domains of carbon that serve as anchoring or nucleation sites for platinum atoms. These results were compared with the literature data, and it turns out that this type of strong metal support interaction (SMSI) modification is favorably induced by UV–VIS irradiation and outperforms Pt-M materials to some extent. Either for HOR or ORR, it is shown that non-noble metals not only act as a surrogate metal for Pt utilization by inducing a compressive stress effect between the Pt atoms in the outermost layer but also participate in the electrocatalytic reaction. This information is important to understand and develop structures with the Pt/C catalyst for the manufacture of electrode materials in the alkaline medium. Related Articles | Metrics | Comments（0） Select Engineering Gas–Solid–Liquid Triple-Phase Interfaces for Electrochemical Energy Conversion Reactions Chen-Chen Weng, Xian-Wei Lv, Jin-Tao Ren, Tian-Yi Ma, Zhong-Yong Yuan Electrochemical Energy Reviews    2022, 5 (S1): 19-.   DOI: 10.1007/s41918-022-00133-x Abstract （326）      PDF       Knowledge map    Save The fundamental water cycle, carbon cycle and nitrogen cycle relying on heterogeneous gas-involving electrocatalytic processes have attracted extensive attention due to their critical contributions to clean, sustainable and energy-environmental electrochemical devices. The development of electrocatalytic materials has afforded gradually improved electrocatalytic reaction efficiency and increasingly promising implementation of electrochemical techniques. In gas-involving electrocatalytic reactions, apart from the intrinsic reaction kinetics, the microenvironment at the triple-phase interfaces of the solid catalyst, liquid electrolyte and gaseous reactant or product under reaction conditions can exert a significant effect on the eventual electrochemical performance since the key issues, including mass transport, electron conduction and accessibility of active sites, are highly sensitive to the electrocatalytic processes. Herein, we systematically summarize the up-to-date progress in energy-related electrocatalysts based on gas-liquid-solid triple-phase interface engineering in terms of an active-site-enriched surface, decent gas wettability and electrolyte infiltration and favorable electronic conductivity. To establish universal theory-structure-function relationships based on triple-phase interface engineering, the corresponding insightful understanding, architecture design/constituent regulation of electrocatalytic materials and admirable electrocatalytic activity are discussed, simultaneously revealing the practical energy-related applications in water electrolyzers, metal-based batteries and fuel cells. Finally, the remaining challenges, possible opportunities and future perspectives are highlighted. Related Articles | Metrics | Comments（0） Select Understanding the Mechanism of the Oxygen Evolution Reaction with Consideration of Spin Xiaoning Li, Zhenxiang Cheng, Xiaolin Wang Electrochemical Energy Reviews    2021, 4 (1): 136-145.   DOI: 10.1007/s41918-020-00084-1 Abstract （2036）      PDF       Knowledge map    Save The oxygen evolution reaction (OER) with its intractably high overpotentials is the rate-limiting step in many devices, including rechargeable metal-air batteries, water electrolysis systems and solar fuel devices. Correspondingly, spin state transitions from spin singlet OH-/H2O reactants to spin triplet O2 product have not yet received enough attention. In view of this, this article will discuss electron behaviours during OER by taking into consideration of spin attribute. The main conclusion is that, regardless of the possible adopted mechanisms (the adsorbate evolution mechanism or the lattice oxygen mechanism), the underlying rationale of OER is that three in four electrons being extracted from adsorbates should be in the same spin direction before O=O formation, superimposing high requirements on the spin structure of electrocatalysts. Therefore, upon fully understanding of the OER mechanism with considerations of spin, the awareness of the coupling between spin, charge, orbital and lattice parameters is necessary in the optimization of geometric and electronic structures in transition metal systems. Based on this, this article will discuss the possible dependency of OER efficiency on the electrocatalyst spin configuration, and the relevance of well-recognized factors with spin, including the crystal field, coordination, oxidation, bonding, the eg electron number, conductivity and magnetism. It is hoped that this article will clarify the underlying physics of OER to provide rational guidance for more effective design of energy conversion electrocatalysts. Full-text：https://link.springer.com/article/10.1007/s41918-020-00084-1 Related Articles | Metrics | Comments（0） Select In Situ Transmission Electron Microscopy Studies of Electrochemical Reaction Mechanisms in Rechargeable Batteries Xiaoyu Wu, Songmei Li, Bin Yang, Chongmin Wang Electrochemical Energy Reviews    2019, 2 (3): 467-491.   DOI: 10.1007/s41918-019-00046-2 Abstract （809）            Knowledge map    Save Rechargeable batteries dominate the energy storage market of portable electronics, electric vehicles and stationary grids, and corresponding performance advancements are closely related to the fundamental understanding of electrochemical reaction mechanisms and their correlation with structural and chemical evolutions of battery components. Through advancements in aberration-corrected transmission electron microscopy (TEM) techniques for signifcantly enhanced spatial resolution, in situ TEM techniques in which a nanobattery assembly is integrated into the system can allow for the direct real-time probing of structural and chemical evolutions of battery components under dynamic operating conditions. Here, open-cell in situ TEM confgurations can provide the atomic resolution imaging of the intrinsic response of materials to ion insertion or extraction, whereas the development of sealed liquid cells can provide new avenues for the observation of electrochemical processes and electrode-electrolyte interface reactions that are relevant to real battery systems. And because of these recent developments in in situ TEM techniques, this review will present recent key progress in the utilization of in situ TEM to reveal new sciences in rechargeable batteries, including complex reaction mechanisms, structural and chemical evolutions of battery materials and their correlation with battery performances. In addition, scientifc insights revealed by in situ TEM studies will be discussed to provide guiding principles for the design of better electrode materials for rechargeable batteries. And challenges and new opportunities will also be discussed. Full-text：https://link.springer.com/article/10.1007/s41918-019-00046-2/fulltext.html Related Articles | Metrics | Comments（0） Select Li-Rich Layered Oxides and Their Practical Challenges: Recent Progress and Perspectives Sijiang Hu, Anoop. S. Pillai, Gemeng Liang, Wei Kong Pang, Hongqiang Wang, Qingyu Li, Zaiping Guo Electrochemical Energy Reviews    2019, 2 (2): 277-311.   DOI: 10.1007/s41918-019-00032-8 Abstract （830）      PDF       Knowledge map    Save Lithium-rich layered oxides (LLOs), also known as Li1+xM1-xO2 or xLi2MnO3-(1-x)LiMO2 (M=Ni, Co, Mn), have been regarded as some of the highest capacity lithium cathodes and have attracted increasing attention from battery researchers and engineers in recent years. This is because LLOs possess maximum possible capacities of~280 to 310 mAh g-1 with a high working potential of~3.7 V (vs. Li+/Li0) and an astounding energy density of~900 Wh kg-1. Despite these promising properties, these technologically important cathodes have not yet been successfully commercialized due to low initial Coulombic efciency, poor rate capabilities and gradual capacity/voltage fade during electrochemical cycling as well as further complications from continuous structural changes during cycling. Here, researchers have concluded that these issues mainly originate from the electrochemical activation of Li2MnO3 components, which, although it provides anomalously high capacity performances, also causes associated complex anionic redox activities of O and irreversible structural and phase transformations during charging at potentials greater than 4.5 V (vs. Li+/Li0). To provide perspectives, this review will summarize various attempts made towards addressing these issues and present the connections between electrochemical properties and structural change. In addition, this review will discuss redox chemistries and mechanistic behaviours during cycling and will provide future research directions to guide the commercialization of LLOs. Full-text：https://link.springer.com/article/10.1007/s41918-019-00032-8/fulltext.html Related Articles | Metrics | Comments（0） Select The Hydrogen Oxidation Reaction in Alkaline Medium: An Overview Carlos Augusto Campos-Roldán, Nicolas Alonso-Vante Electrochemical Energy Reviews    2019, 2 (2): 312-331.   DOI: 10.1007/s41918-019-00034-6 Abstract （969）      PDF       Knowledge map    Save The recent advances in electrocatalysis for the hydrogen evolution reactions in acid and alkaline media are carefully reviewed. In this sense, this short review focuses on precious and non-precious catalytic centers. The recent development of HOR electrocatalysts with novel structures and compositions is highlighted. The understandings of the correlation between the activity and the shape, size, composition, and synthesis methods are summarized. The research directions, e.g., on the further development of more active, more stable, and less expensive electrocatalysts for the anion-exchange membranes for the alkaline fuel cell technology are provided. In this context, positive perspectives to overcome the high kinetic barriers encountered in alkaline medium can be expected in the years to come. Full-text：https://link.springer.com/article/10.1007/s41918-019-00034-6/fulltext.html Related Articles | Metrics | Comments（0） Select 3D Hierarchical Porous Graphene-Based Energy Materials: Synthesis, Functionalization, and Application in Energy Storage and Conversion Cheng Tang, Hao-Fan Wang, Jia-Qi Huang, Weizhong Qian, Fei Wei, Shi-Zhang Qiao, Qiang Zhang Electrochemical Energy Reviews    2019, 2 (2): 332-371.   DOI: 10.1007/s41918-019-00033-7 Abstract （739）      PDF       Knowledge map    Save The rational development of efective energy materials is crucial to the sustainable growth of society. Here, 3D hierarchical porous graphene (hpG)-based materials with micro-, meso-, and macroporous features have recently attracted extensive research eforts due to unique porosities, controllable synthesis, versatile functionalization, favorable mass/electron transport, and superior performances in which corresponding electrochemical performances are strongly dependent on the nature of the building blocks and structural hierarchy of the assemblies. In this review, recent achievements in the controllable synthesis, versatile functionalization, and device application of 3D hpG-based energy materials will be summarized, including controllable and facile synthesis through chemical vapor deposition on 3D porous templates, post-assembly/treatment of graphene oxide nanosheets, and templated polymerization. In addition, graphene material functionalization through heteroatom doping, spatially confned decoration of active nanoparticles, and surface hybridization of graphene-analogous components to enhance electrochemical properties will be discussed. Furthermore, applications of 3D hpG materials in various electrochemical energy storage and conversion systems will be summarized, including lithium-ion batteries, lithium-sulfur batteries, lithium metal anodes, oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, and nitrogen reduction reaction. Overall, this review will comprehensively present the property advantages, design principles and synthesis strategies of 3D hpG-based energy materials and provide guidance in the development of various 2D graphene-analogous materials and nanomaterials for advanced electrochemical energy storage and conversion systems. Full-text：https://link.springer.com/article/10.1007/s41918-019-00033-7/fulltext.html Related Articles | Metrics | Comments（0） Select In Situ and Surface-Enhanced Raman Spectroscopy Study of Electrode Materials in Solid Oxide Fuel Cells Xiaxi Li, Kevin Blinn, Dongchang Chen, Meilin Liu Electrochemical Energy Reviews    2018, 1 (3): 433-459.   DOI: 10.1007/s41918-018-0017-9 Abstract （1396）      PDF       Knowledge map    Save Solid oxide fuel cells (SOFCs) represent next-generation energy sources with high energy conversion efciencies, low pollutant emissions, good fexibility with a wide variety of fuels, and excellent modularity suitable for distributed power generation. As an electrochemical energy conversion device, the SOFC's performance and reliability depend sensitively on the catalytic activity and stability of electrode materials. To date, however, the development of electrode materials and microstructures is still based largely on trial-and-error methods because of the inadequate understanding of electrode process mechanisms. Therefore, the identifcation of key descriptors/properties for electrode materials or functional heterogeneous interfaces, especially under in situ/operando conditions, may provide guidance for the design of optimal electrode materials and microstructures. Here, Raman spectroscopy is ideally suited for the probing and mapping of chemical species present on electrode surfaces under operating conditions. And to boost the sensitivity toward electrode surface species, the surfaceenhanced Raman spectroscopy (SERS) technique can be employed, in which thermally robust SERS probes (e.g., Ag@SiO2 core-shell nanoparticles) are designed to make in situ/operando analysis possible. This review summarizes recent progresses in the investigation of SOFC electrode materials through Raman spectroscopic techniques, including topics of early stage carbon deposition (coking), coking-resistant anode modifcation, sulfur poisoning, and cathode degradation. In addition, future perspectives for utilizing the in situ/operando SERS for investigations of other electrochemical surfaces and interfaces are also discussed. Full-text：https://link.springer.com/article/10.1007/s41918-018-0017-9 Related Articles | Metrics | Comments（0）