再生氢氧燃料电池

再生氢氧燃料电池作为一种比能量高、使用寿命长的新型贮能电池引起了世界各国的广泛重视,作为贮能电池已通过航天模拟实验,并可望转为民用。本文介绍了再生氢氧燃料电池的原理、结构、分类及其特点,并对其主要技术问题及发展方向进行了分析。     

Progress of transition metal chalcogenides as efficient electrocatalysts for energy conversion

The continuous excessive usage of fossil fuels has resulted in its fast depletion, leading to an escalating energy crisis as well as several environmental issues leading to increased research towards sustainable energy conversion. Electrocatalysts play crucial role in the development of numerous novel energy conversion devices, including fuel cells and solar fuel generators. In particular, high-efficiency and cost-effective catalysts are required for large-scale implementation of these new devices. Over the last few years, transition metal chalcogenides have emerged as highly efficient electrocatalysts for several electrochemical devices such as water splitting, carbon dioxide electroreduction, and, solar energy converters. These transition metal chalcogenides exhibit high electrochemical tunability, abundant active sites, and superior electrical conductivity. Hence, they have been actively explored for various electrocatalytic activities. Herein, we have provided comprehensive review of transition-metal chalcogenide electrocatalysts for hydrogen evolution, oxygen evolution, and carbon dioxide reduction and illustrated structure–property correlation that increases their catalytic activity.     

电化学阻抗谱弛豫时间分布基础

电化学阻抗谱（EIS）是一种高效的原位/非原位电化学表征技术,已在电化学能源领域得到广泛应用,如用于锂离子电池、超级电容器、燃料电池等材料及器件性能的诊断和优化. 弛豫时间分布（DRT）是一种不依赖于研究对象先验知识的EIS解析技术,可用于分离和解析EIS中高度重叠的物理化学过程. 为了促进DRT解析技术的应用和推广,本文详细阐述了如下问题： 1） DRT解析原理、实现算法及重要扩展; 2） 典型电路基元的DRT解析分析; 3） DRT的具体实现及在电化学能源中的典型应用举例; 4）DRT解析技术研究进展、存在问题及发展趋势.     

Polyelectrolyte Membranes Based on Sulfonated Syndiotactic Polystyrene in Its Clathrate Form

Recently, more and more attention has been focused on new techniques for energy production also in view of environmental problems. A noticeable device is small fuel cell that converts chemical energy into electric energy by electrochemical reaction of hydrogen with oxygen, and exhibits a high-energy efficiency. Conventional small fuel cells have been classified into phosphoric acid-type fuel cells, molten carbonate-type fuel cells, solid oxide-type fuel cells, solid polymer type fuel cells, etc., according to the type of electrolyte used. The target of this work is the development of a new process to build up polyelectrolyte membranes, for polymer type fuel cell (PEM), by sulfonating syndiotactic polystyrene in its clathrate form. The polyelectrolyte membranes of this paper are inexpensive and exhibit good long-term stability and ion exchange capability.     

A journey on the electrochemical road to sustainability

As the nations of the world continue to develop, their industrialization and growing populations will require increasing amounts of energy. Yet, global energy consumption, even at present levels, has already given rise to major concerns over the security of future supplies, together with the attendant twin problems of environmental degradation and climate change. Accordingly, countries are examining a whole range of new policies and technology issues to make their energy futures ??sustainable??, that is, to maintain economic growth and cultural values whilst providing energy security and environmental protection. A step in the right direction is to place electrochemical power sources??serviceable, efficient and clean technology??at the cutting edge of energy strategies, regardless of the relatively low price of such traditional fuels as coal, mineral oil and natural gas. Following a chronicle of the events that led up to the discovery of batteries and fuel cells, the paper discusses the application of these devices as important technology for shifting primary energy demand away from fossil fuels and towards renewable sources that are more abundant, less expensive and/or more environmentally benign. Finally, consideration is given to the idea of introducing hydrogen as the universal vector for conveying renewable forms of energy and also as the ultimate non-polluting fuel. Fuel cells are the key enabling technology for a hydrogen economy. As requested, the paper opens with a brief account of the circumstances by which the author joined others on a fascinating journey on the electrochemical road to sustainability.     

Silica sol–gel chemistry: creating materials and architectures for energy generation and storage

There is widespread recognition that the use of energy in the twenty-first century must be sustainable. Because of its extraordinary flexibility, silica sol–gel chemistry offers the opportunity to create the novel materials and architectures which can lead to significant advances in renewable energy and energy storage technologies. In this paper, we review some of the significant contributions of silica sol–gel chemistry to these fields with particular emphasis on electrolytes and separators where sol–gel approaches to functionalization and encapsulation have been of central importance. Examples are presented in the areas of dye-sensitized solar cells, biofuel cells, proton exchange membrane fuel cells, redox flow batteries and electrochemical energy storage. Original work is also included for the sol–gel encapsulation of a room temperature ionic liquid to create a solid state electrolyte for electrochemical capacitors. In view of the critical importance of energy and the versatility of the sol–gel process, we expect the sol–gel field to play an increasingly important role in the development of sustainable energy generation and storage technologies.     

Catalytic Activity Towards Hydrogen Evolution Dependent of the Degree of Conjugation and Absorption of Six Organic Chromophores

Conjugated materials can, in many cases, absorb visible light because of their delocalized π electron system. Such materials have been widely used as a photoactive layers in organic photovoltaic devices and as photosensitizers in dye-sensitized solar cells. Additionally, these materials have been reported for applications in solar fuel production, working as photocatalysts for the hydrogen evolution reaction (HER). The synthesis of three flexible vinyl groups-containing chromophores is reported. The catalytic activity towards hydrogen evolution of these chromophores has been investigated and compared to their non-vinyl-containing analogues. The catalytic effect was confirmed using two different approaches: electrochemical, using the chromophores to modify a working electrode, and photocatalytic, using the chromophores combined with platinum nanoparticles. A relationship between the degree of conjugation and the catalytic activity of the chromophores has been observed with the electrochemical method, while a relationship between the UV absorption in the solid state and the photocatalytic effect with platinum nanoparticles was observed.     

Recent Developments in Carbon-Based Nanocomposites for Fuel Cell Applications: A Review

Carbon-based nanocomposites have developed as the most promising and emerging materials in nanoscience and technology during the last several years. They are microscopic materials that range in size from 1 to 100 nanometers. They may be distinguished from bulk materials by their size, shape, increased surface-to-volume ratio, and unique physical and chemical characteristics. Carbon nanocomposite matrixes are often created by combining more than two distinct solid phase types. The nanocomposites that were constructed exhibit unique properties, such as significantly enhanced toughness, mechanical strength, and thermal/electrochemical conductivity. As a result of these advantages, nanocomposites have been used in a variety of applications, including catalysts, electrochemical sensors, biosensors, and energy storage devices, among others. This study focuses on the usage of several forms of carbon nanomaterials, such as carbon aerogels, carbon nanofibers, graphene, carbon nanotubes, and fullerenes, in the development of hydrogen fuel cells. These fuel cells have been successfully employed in numerous commercial sectors in recent years, notably in the car industry, due to their cost-effectiveness, eco-friendliness, and long-cyclic durability. Further; we discuss the principles, reaction mechanisms, and cyclic stability of the fuel cells and also new strategies and future challenges related to the development of viable fuel cells.     

Advances in efficient electrocatalysts based on layered double hydroxides and their derivatives

The explore and development of electrocatalysts have gained significant attention due to their indispensable status in energy storage and conversion systems, such as fuel cells, metal–air batteries and solar water splitting cells. Layered double hydroxides(LDHs) and their derivatives(e.g., transition metal alloys, oxides, sulfides, nitrides and phosphides) have been adopted as catalysts for various electrochemical reactions, such as oxygen reduction, oxygen evolution, hydrogen evolution, and CO_2 reduction, which show excellent activity and remarkable durability in electrocatalytic process. In this review, the synthesis strategies, structural characters and electrochemical performances for the LDHs and their derivatives are described. In addition, we also discussed the effect of electronic and geometry structures to their electrocatalytic activity. The further development of high-performance electrocatalysts based on LDHs and their derivatives is covered by both a short summary and future outlook from the viewpoint of the material design and practical application.     

A comprehensive three-dimensional modeling of an internal reforming planar solid oxide fuel cell with different interconnect designs

Development of low-emission or zero-emission power generation systems is one of the most important subjects humanity is dealing with. Among different under development technologies and energy systems, a solid oxide fuel cell (SOFC) is an efficient and low-emission energy conversion device that is passing its research and development career. The current study aims to investigate a hydrocarbon fueled anode-supported planar-type SOFC due to simpler geometry, higher power density, and low overpotentials. In this study, electric performance of a SOFC with different interconnect designs under different operating conditions, such as operating voltage, channel inlet temperature, pre-reforming rate of methane, and inlet fuel and air velocity, has been investigated by use of a three-dimensional model considering complicated systems of equations: species mass conservation, first law of thermodynamics, conservation of momentum, and non-linear electrochemical models including multi-specious diffusion. It has been concluded that at a given voltage, inlet temperature, inlet air and fuel velocity, and pre-reforming rate, wider gas channels help to more uniform distribution and better penetration of reactant gases. Therefore, considering low-concentration polarization as an object, narrow ribs are preferred over wide ribs. By increasing the rate of the electrochemical reaction, the current and power density and subsequently the temperature difference increase but the fuel consumption in all cases has almost a decreasing trend. Also, it has been found that increasing inlet air velocity has little effect on current and power density but because of more cooling effect, it reduces the temperature difference and fuel consumption coefficient. On the other hand, increasing the inlet temperature has no meaningful effect on the temperature difference along the channels.

     

Molecular Engineering of Boryl Oxasmaragdyrins through Peripheral Modification: Structure–Efficiency Relationship

Expanded porphyrins with the absorption profile down to the infrared region through increased π‐conjugation are suitable candidates for a low energy sensitizer. Oxasmaragdyrin boron complexes, a class of aromatic‐core‐modified expanded porphyrin with 22 π‐electrons, have been recently utilized as an efficient low energy sensitizer in dye‐sensitized solar cells. In this paper, we have prepared a series of eight novel boryl oxasmaragdyrins through molecular engineering on the periphery and their overall photovoltaic performances in dye‐sensitized solar cells are evaluated. With the help of photophysical, electrochemical, and photovoltaic studies, it is revealed that molecular structure, especially the number and position of the donor–acceptor groups play a pivotal role in their photovoltaic performance. Presence of the two well‐separated split Soret bands in the 400–500 nm region of UV/Vis spectrum ensures broader coverage of absorption wavelengths. Even though the two‐anchoring‐group dyes ( SM5 – SM8 ) bind strongly to TiO₂ compared to one‐anchoring‐group dyes ( SM1 – SM4 ), the latter have superior photovoltaic performance than the former. Dye SM1 , with two hexyloxyphenyl donors and one carboxylic acid anchor showed the best overall conversion efficiency of 4.36 % (J_SC=10.91 mA cm^?2; V_OC=0.59 V; FF=0.68). This effective modulation of photovoltaic performance through structural engineering of the dyes will serve as a guideline for the future design of efficient low energy light‐harvesting sensitizers.     

Comparison of characteristics of solid oxide fuel cells with YSZ and CGO film solid electrolytes formed using magnetron sputtering technique

The work describes the methods of manufacturing single cells of solid oxide fuel cell (SOFC) with thin–film YSZ and CGO electrolytes and also with the bilayer YSZ/CGO electrolyte. Formation of YSZ and CGO films on the supporting NiO–YSZ anode of SOFC was carried out using the combined electron–ionic–plasma deposition technique. The microstructure and phase composition of the formed coatings are studied and also comparative analysis of electrochemical characteristics of single fuel cells with different electrolytes is performed. It is shown that the maximum power density of 1.35 W/cm² at the temperature of 800°C is obtained for the cell with bilayer YSZ/CGO electrolyte. However, the highest performance at lower working temperatures (650–700°C) is characteristic for the fuel cell with single–layer CGO electrolyte; its power density is 600–650 mW/cm².     

《碳纳米材料电化学》专辑序言 ——方兴未艾的电化学能量转换和存储先进材料和技术

可以预见,在相当一段时期内,能源和环境将是全球发展的两大主题. 其实,人类对能源的获取方式将对地球的生态环境和人类未来的生存状态和生活方式产生重要影响. 正因为如此,世界各国正在大力发展可再生能源和清洁能源. 电化学能源是将化学能高效转变为电能的一种能量转换方式,它历史悠久,但不断被改进和创新,尤其是近年来得到了较快的发展. 目前,电化学能源转换和存储器件主要包括一次电池（如锌锰电池等）、二次电池（如铅酸电池、镍氢电池、锂离子电池等）、燃料电池、金属-空气电池以及超级电容器等. 电化学能源和其它可再生能源相互补充、交叉利用将是未来清洁能源的主要发展方向.     

Towards large-scale, fully ab initio calculations of ionic liquids

Ionic liquids have attracted a substantial amount of interest as replacement of traditional electrolytes in high efficiency electrochemical devices for generation and storage of energy due to their superior physical and chemical properties, especially low volatility and high electrochemical stability. For enhanced performance of the electrochemical devices ionic liquids are required to be highly conductive and low viscous. Long-range Coulomb and short-range dispersion interactions between ions affect physical and chemical properties of ionic liquids in a very complex way, thus preventing direct correlations to the chemical structure. Considering a vast combination of available cations and anions that can be used to synthesize ionic liquids, development of predictive theoretical approaches that allow for accurate tailoring of their physical properties has become crucial to further enhance the performance of electrochemical devices such as lithium batteries, fuel and solar cells. This perspective article gives a thorough overview of current theoretical approaches applied for studying thermodynamic (melting point and enthalpy of vapourisation) and transport (conductivity and viscosity) properties of ionic liquids, emphasizing their reliability and limitations. Strategies for improving predictive power and versatility of existing theoretical approaches are also outlined.     

电化学双电层电容器用新型炭材料及其应用前景

活性炭是目前使用最为广泛的一种电化学双电层电容器（EDLC）的电极材料,但其固有的缺点制约了EDLC性能的进一步提高。用新型高性能炭电极材料可使EDLC比能量和比功率性能进一步提高。这些新型炭材料包括基于石墨层状结构的纳米门炭,基于碳纳米管阵列结构的毛皮炭,通过高温置换反应制备的骨架炭以及电极可整体成型的纳米孔玻态炭。本文介绍了这些炭材料的电化学特性及其在电化学双电层电容器中的应用,指出用这4种新型炭材料制备EDLC的比能量或比功率性能远高于目前活性炭基EDLC,具有良好的应用前景。     

单元素二维材料及其衍生物作为电荷传输层在太阳能电池中应用的研究进展

随着环境污染的日益严重和能源危机的不断加剧, 新能源的开发和利用逐渐成为研究的重点. 在各种已开发的绿色能源技术中, 光伏发电是一种非常有前景的技术. 尽管传统硅基太阳能电池已取得长足进步, 但其性价比与传统能源相比仍有差距. 因此, 开发低成本高效太阳能电池迫在眉睫, 但新型太阳能电池的应用仍受到稳定性差与效率较低的双重考验. 在前期研究基础上, 人们将化学和物理性能优异的单元素二维材料及其衍生物作为电荷传输层引入太阳能电池中, 在改善电池稳定性及提升效率方面取得了积极的效果. 本文综合评述了纳米级单元素二维材料及其衍生物作为太阳能电池电荷传输层的相关研究进展. 这些单元素材料的引入使得所研究的太阳能电池效率得到了显著的提高, 同时也证明该类型电荷传输层的构建为满足现代社会能源需求提供了新技术平台. 文章最后讨论了单元素二维材料在太阳能电池中应用面临的关键挑战和发展前景.     

Nanorobots: The Ultimate Wireless Self‐Propelled Sensing and Actuating Devices

Natural motor proteins, “bionanorobots,” have inspired researchers to develop artificial nanomachines (nanorobots) able to move autonomously by the conversion of chemical to mechanical energy. Such artificial nanorobots are self‐propelled by the electrochemical decomposition of the fuel (up to now, hydrogen peroxide). Several approaches have been developed to provide nanorobots with some functionality, such as for controlling their movement, increasing their power output, or transporting different cargo. In this Focus Review we will discuss the recent advances in nanorobots based on metallic nanowires, which can sense, deliver, and actuate in complex environments, looking towards real applications in the not‐too‐distant future.     

Bridging X-ray computed tomography and computational modeling for electrochemical energy-conversion and –storage

X-ray imaging techniques are powerful tools for understanding morphology, transport and even reactions within the electrochemical energy systems. Transmission X-ray microscopy (TXM) and X-ray computed tomography (CT) have been widely used in ex-situ studies to probe morphology of electrochemical energy materials. Emerging operando studies highlight the possibility of imaging energy materials and devices under realistic operating conditions. We present an overview of recent advances in the X-ray CT methods with application to fuel cells, batteries and other energy technologies, and describe how the information obtained with multimodal imaging is used within the multi-scale computational models. Overall, the progress in imaging outran the modeling progress, and current models are limited in their utility to incorporate vast amount of multimodal image data.     

Small molecule semiconductors for high-efficiency organic photovoltaics

Organic photovoltaic cells (OPVs) are a promising cost-effective alternative to silicon-based solar cells, and possess light-weight, low-cost, and flexibility advantages. Significant progress has been achieved in the development of novel photovoltaic materials and device structures in the last decade. Nowadays small molecular semiconductors for OPVs have attracted considerable attention, due to their advantages over their polymer counterparts, including well-defined molecular structure, definite molecular weight, and high purity without batch to batch variations. The highest power conversion efficiencies of OPVs based on small molecular donor/fullerene acceptors or polymeric donor/fullerene acceptors are up to 6.7% and 8.3%, respectively, and meanwhile nonfullerene acceptors have also exhibited some promising results. In this review we summarize the developments in small molecular donors, acceptors (fullerene derivatives and nonfullerene molecules), and donor-acceptor dyad systems for high-performance multilayer, bulk heterojunction, and single-component OPVs. We focus on correlations of molecular chemical structures with properties, such as absorption, energy levels, charge mobilities, and photovoltaic performances. This structure-property relationship analysis may guide rational structural design and evaluation of photovoltaic materials (253 references).