Electrochemical Kinetics at the Diamond Electrode/Solution Interface

CTS-9509842研究了金刚石(掺杂和非掺杂；单晶和多晶)的电化学动力学行为，并评价了其作为电化学技术电极材料的潜力。探讨了影响金刚石薄膜电化学行为的因素，包括掺杂水平、掺杂类型、表面处理、等离子体刻蚀、退火处理、金刚石形貌和石墨化含量。采用微波等离子体和热丝技术在钼硅、玻碳、单晶金刚石和石墨衬底上生长了不同表面形貌的未掺杂和掺杂金刚石薄膜。用交流阻抗和直流极化技术测定了金刚石电极在0.5M盐溶液中的阳极和阴极转移系数、腐蚀速率、交换电流密度、双电层电容、膜电阻、极化电阻和/或电荷转移电阻。用伏安技术研究了模型体系的氧化还原行为，金刚石电极在不同电解液中的工作电位范围，以及掺杂金刚石和铂/铱或二氧化Ru在金刚石上的电催化作用。人们普遍认为，工业电化学的进一步发展将需要新的电极材料。戴蒙德是一个很有前途的候选人，但尚未得到证实。***

ABSTRACT CTS-9509842 This is a study of the electrochemical kinetic behavior of diamond (doped and undoped; single-crystal and polycrystalline) and an evaluation of its potential as an electrode material in electrochemical technology. Factors influencing the electrochemical behavior of diamond film are explored, including dopant levels, type of dopants, surface pretreatment, plasma etching, annealing treatments, diamond morphology, and graphitic content. Undoped and doped diamond thin films with various surface morphologies are grown on molybdenum silicon, glassy carbon, single-crystal diamond, and graphite substrates by microwave plasma and hot-filament techniques. Anodic and cathodic transfer coefficients, corrosion rate, exchange current density, double-layer capacitance, film resistance, polarization resistance, and/or charge-transfer resistance of diamond electrodes in a 0.5 M salt solution are determined using AC impedance and DC polarization techniques. Voltammetric techniques are used to study redox behavior of model systems, working potential limits of diamond electrodes in various electrolytes, and electrocatalysis by doped diamond and by platinum/iridium or ruthenium dioxide on diamond. It is generally accepted that further advances in industrial electrochemistry will require new electrode materials. Diamond is a promising, but as yet unproven, candidate. ***