双极性电化学的概述及研究进展

作为近年来快速发展的一种便携、阵列、简单的电化学体系,双极性电化学在分析检测、材料制备、物质筛选等领域受到研究者的青睐。简要介绍了双极性电化学的特点,介绍了双极性电极（BPE）体系的2种主要装置：开放性BPE和封闭性BPE。并以开放性BPE体系为例,着重阐述了BPE体系的电化学原理。分别介绍了BPE的极性与驱动电极的关系、BPE体系中的电压及电流的分布,为BPE体系的研究者提供简要的理论基础。此外,还列举了BPE体系在分析检测、材料制备和物质筛选等领域的应用。     

Bipolar Electrochemistry Exfoliation of Layered Metal Chalcogenides Sb2S3 and Bi2S3 and their Hydrogen Evolution Applications

Efficient exfoliation and downsizing of Sb₂S₃ and Bi₂S₃ layered compounds by using scalable bipolar electrochemistry on their suspensions in aqueous media are here demonstrated. The resulting samples were characterized in detail by transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy; their electrochemistry toward hydrogen evolution was also investigated. Hydrogen evolution ability of exfoliated Sb₂S₃ and Bi₂S₃ was investigated and compared to the bulk counterparts.     

Electrode Materials in Modern Organic Electrochemistry

The choice of electrode material is critical for achieving optimal yields and selectivity in synthetic organic electrochemistry. The material imparts significant influence on the kinetics and thermodynamics of electron transfer, and frequently defines the success or failure of a transformation. Electrode processes are complex and so the choice of a material is often empirical and the underlying mechanisms and rationale for success are unknown. In this review, we aim to highlight recent instances of electrode choice where rationale is offered, which should aid future reaction development.     

Electrochemistry in solids prepared by sol-gel processes

Sol-gel chemistry provides a route to preparing inorganic polymers with ionically conducting properties by room temperature synthetic routes. The products, which are rigid solids, are well-suited as media for conventional electrochemical techniques such as cyclic voltammetry. This property, when combined with their ability to host a wide variety of species, has allowed development of a variety of devices of interest in electrochemistry and analytical chemistry. Examples include cathodes for fuels cells, electrochromic devices, biosensors, and amperometric sensors for analytes in the gas phase. In this review, the emphasis will be on reported applications to analytical chemistry; however, studies on the general properties of these materials and on their use in electrochemical science also will be summarized because they may provide the basis for further development of sensors.     

结合实际发展电化学科学─—武汉大学电化学研究室工作简介

结合实际发展电化学科学─—武汉大学电化学研究室工作简介查全性,陆君涛（武汉大学化学系电化学研究室,武汉４３００７２）在物理化学的众多分支学科中,电化学长期保持良好的发展势头。除了电化学所研究的体系（溶液、电极／溶液界面等）具有广泛的基础意义外,促使电...     

Cosmetic Electrochemistry II: Rapid and Facile Production of Metallic Electrocatalytic Ensembles

We demonstrate a facile methodology for the production of metallic electrocatalytic microdomain ensembles for a range of analytical sensing challenges. A commercially available off‐the‐shelf cosmetic product can change the voltammetric characteristics of a metallic macro‐electrode created electrolytically into that of a random ensemble of metallic microelectrode domains. Proof‐of‐concept is shown for three examples: a palladium ensemble for hydrazine sensing, a gold ensemble for arsenic(III) detection via anodic stripping voltammetry and platinum ensembles for the direct oxidation of arsenic(III). Last we demonstrate that the fabrication of metallic microdomains can be simplified by sputter coating screen printed electrochemical sensing platforms which are beneficially constructed using this cosmetic methodology. Given the facile fabrication and low cost of the underlying electrode substrate and the cosmetic modifier, the widespread implementation of this novel fabrication methodology is expected.     

新型二维纳米材料在电化学领域的应用与发展

以石墨烯为代表的新型二维纳米材料具有独特的结构和优异的电子特性,在电化学各领域具有巨大的应用潜力。 本综述总结了新型二维纳米材料在电化学各领域(能源存储、能源转化和电化学传感)的研究现状和存在的问题。 展望了二维纳米材料在电化学领域的发展趋势。     

A Packed Graphite Cell for Thin-Layer Electrochemistry

Abstract

A thin-layer electrochemical cell, which consists of a bed of graphite granules, is described and evaluated for chronopotentiometric experiments. The dependence of transition time on concentration is linear (within 3%) for a single component and the transition time of a component is independent of the concentrations of other electroactive materials in the solution.     

熔盐电化学创新研究——武汉大学电化学研究中心熔盐电化学研究工作简介

简要介绍近3年武汉大学电化学研究中心在熔盐电化学方面的若干研究进展:1)熔盐电解固态化合物制备单质硅及其合金以及无机功能材料;2)适于高温熔盐的全密封长寿命Ag/AgCl参比电极和可负载微量粉末的金属腔(坑)工作电极新技术;3)“三相界线电化学”新概念以及描述三相界线在薄层固态化合物电解还原过程中扩展变化的薄层模型.     

细胞电化学的研究进展

本文从细胞化学组成的电化学研究、细胞生物生理行为的电化学研究、细胞分析传感器、细胞的电场和电磁场生化效应及其应用等4 个方面介绍细胞电化学的原理和方法。综述了近年来细胞电化学的研究内容和最新进展, 探讨了细胞电化学的发展方向。     

Electrochemically Generated Gradients

This review surveys recent developments in the field of electrochemically generated gradients. The gradual variation of properties, which is a key characteristic of gradients, is of eminent importance in technology, for example, directional wetting, as well as biology, for example, chemotaxis. Electrochemical techniques offer many benefits, such as the generation of dynamic solution and surface gradients, integration with electronics, and compatibility with automation. An overview is given of newly developed methods, from purely electrochemical techniques to the combination of electrochemistry with other methods. Electrochemically fabricated gradients are employed extensively for biological and technological applications, such as high‐throughput screening, high‐throughput deposition, and device development, all of which are covered herein. Especially promising are developments towards the study and control of dynamic phenomena, such as the directional motion of molecules, droplets, and cells.     

有机电化学合成简谈

本文简要介绍了有机电化学合成的体系,研究方法和技术及主要特征。以C=C类物质为例介绍了有机电化学合成中的各类反应,并以己二腈的电合成为例介绍了相应的工业化应用。试图以CO2的电化学固定利用为例介绍了有机电化学合成的研究动向。     

Two-Dimensional MOF and COF Nanosheets: Synthesis and Applications in Electrochemistry

Metal–organic framework (MOF) and covalent organic framework (COF) nanosheets are a new type of two-dimensional (2D) materials with unique design principles and various synthesis methods. They are considered ideal electrochemical devices due to the ultrathin thickness, easily tunable molecular structure, large porosity and other unique properties. There are two common methods to synthesize 2D MOF/COF nanosheets: bottom-up and top-down. The top-down strategy mainly includes ultrasonic assisted exfoliation, electrochemical exfoliation and mechanical exfoliation. Another strategy mainly includes interface synthesis, modulation synthesis, surfactant-assisted synthesis. In this Review, the development of ultrathin 2D nanosheets in the field of electrochemistry (supercapacitors, batteries, oxygen reduction, and hydrogen evolution) is introduced, and their unique dimensional advantages are highlighted.     

A Resettable Keypad Lock with Visible Readout Based on Closed Bipolar Electrochemistry and Electrochromic Poly(3‐methylthiophene) Films

A closed bipolar electrode (BPE) system was developed with electrochromic poly(3‐methylthiophene) (PMT) films electropolymerized on the ITO/rGO electrode as one pole of BPE in the reporting reservoir and the bare ITO electrode as another pole of BPE in the analyte reservoir, in which rGO represents reduced graphene oxide. Under a suitable driving voltage (V_tot), the electrochemical reduction/oxidation of electroactive probes, such as H₂O₂/glutathione (Glu), in the analyte reservoir could induce the reversible color change of PMT films in the reporting reservoir between blue and red. Based on this, a keypad lock with H₂O₂, Glu, and V_tot=?3.0 V as the three inputs and the color change of PMT films as the visible output was established. This system was easily operated and did not need to synthesize the complex compounds or DNA molecules. The security system was easy to reset and could be used repeatedly.     

Flowerlike Vanadium Sesquioxide: Solvothermal Preparation and Electrochemical Properties

A novel 3D hierarchical flowerlike vanadium sesquioxide (V₂O₃) nano/microarchitecture consisting of numerous nanoflakes is prepared via a solvothermal approach followed by an appropriate heating treatment. The as‐obtained nanostructured V₂O₃ flower is characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and transmission electron microscopy (TEM) (or/and high‐resolution TEM, HRTEM), and it is found that the V₂O₃ flower is constructed by single‐crystalline nanoflakes. Furthermore, it is demonstrated that the surface of the flowerlike V₂O₃ material is composed of nanostructured pores, which derive from the adsorption/desorption of nitrogen, and that the pore‐size distribution depends on the unique three‐dimensional interconnection between nanoflakes and on their intrinsic properties. The electrochemical behavior of the V₂O₃ flower for lithium‐ion insertion/extraction in non‐aqueous solution as well as the faradaic capacitance for pesudocapacitors in a neutral aqueous solution are also investigated. A reversible discharge capacity as high as 325 mA h g^?1 is obtained at a current density of 0.02 A g^?1 from a LiClO₄/EC:DEC electrolyte solution (i.e. LiClO₄ in ethyl carbonate and diethyl carbonate). When used as the cathode material of pesudocapacitors in Li₂SO₄, the flowerlike oxide displayed a very high initial capacitance of 218 F g^?1 at a current density of 0.05 A g^?1. We believe that the good performance of the flowerlike V₂O₃ electrode is most probably due to its unique 3D hierarchical nano/microarchitecture, which shows that the electrochemical properties of a cathodic material do not only depend on the oxidation state of that material but also—to a large extent—on its crystalline structure and morphology. The aforementioned properties suggest that the present V₂O₃ flower materials may have a great potential to be employed as electrode materials in rechargeable lithium batteries and pesudocapacitors.     

金刚石薄膜电化学

金刚石由于其特殊的物理与化学性质,早在几百年前就吸引了人们对它的关注.化学气相沉积(chemical vapor deposition,CVD)法制备的高掺杂硼复合多晶金刚石薄膜,为金刚石薄膜在电化学中的应用开辟了新的领域.作为新型碳素电极材料,高掺杂硼复合多晶金刚石薄膜具有许多目前使用的电极材料所不可比拟的优异特性如:宽电化学势窗,低残留电流,极好的电化学稳定性以及表面不易被污染等.本文综述了高掺杂硼复合多晶金刚石薄膜电极在电化学中的几个重要应用,包括电分析、电合成及电化学法处理废水等.     

Electrochemistry at chemically modified graphenes

Electrochemical applications of graphene are of great interest to many researchers as they can potentially lead to crucial technological advancements in fabrication of electrochemical devices for energy production and storage, and highly sensitive sensors. There are many routes towards fabrication of bulk quantities of chemically modified graphenes (CMG) for applications such as electrode materials. Each of them yields different graphene materials with different functionalities and structural defects. Here, we compare the electrochemical properties of five different chemically modified graphenes: graphite oxide, graphene oxide, thermally reduced graphene oxide, chemically reduced graphene oxide, and electrochemically reduced graphene oxide. We characterized these materials using transmission electron microscopy, Raman spectroscopy, high-resolution X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, and cyclic voltammetry, which allowed us to correlate the electrochemical properties with the structural and chemical features of the CMGs. We found that thermally reduced graphene oxide offers the most favorable electrochemical performance among the different materials studied. Our findings have a profound impact for the applications of chemically modified graphenes in electrochemical devices.     

扫描电化学显微镜及其在界面电化学研究中的应用

对扫描电化学显微镜(Scanning Electrochemical Microscope，SECM)的发展及其在界面电化学中的研究应用进行了评述。介绍了SECM的工作原理以及常用的操作模式，并对SECM在液／液界面、固／液界面等方面的应用进行了总结。