(中南大学 冶金与环境学院，长沙410083)
摘 要: 针对电化学冶金提取半导体元素存在的问题，提出采用光电化学冶金的方法来进行半导体元素的电化学沉积提取。结合半导体特性以及光电化学基本理论，阐述光电化学冶金的优势，并以碲提取为例验证光电化学冶金的优越性。结果表明：光电化学沉积过程中，半导体沉积物吸收能量大于其自身带隙宽度的光子后受激发产生光生电子-空穴对，光生电子从半导体流向电解液促进电化学还原，同时光生载流子可减小电阻率和能带弯曲，降低工作电极所分摊的电势差。与常规的电化学沉积相比，光电化学沉积可以强化电极过程、降低槽电压，以及提高沉积速率、电流效率和产能，具有良好的应用前景。最后指出光电化学冶金未来发展可能面临的问题，并对其内涵进行拓展。
关键字: 半导体元素；光照；槽电压；光电化学冶金；电化学沉积
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:Photo-electrometallurgy technique was proposed for electrochemical extraction of semiconductor elements in this work aiming to solve the problems in electrometallurgy of semiconductor elements. Based on knowledge of semiconductor characters and photo-electrochemistry, the advantages of the proposed photo-electrometallurgy technique were revealed, and its superiority was experimentally confirmed by an example of tellurium (Te) electrochemical extraction. The results indicate that the semiconductor deposits can absorb the incident photons with energy larger than its band gap and be excited to generate electron-hole pair. The photon-generated electrons can flow from semiconductor electrode into electrolyte, enhancing the electrochemical reduction rate and the photon-generated-carriers can decrease the resistivity and band bending, reducing the potential drop at electrode. Compared with the traditional electrometallurgy, photo-electrometallurgy shows the advantages in intensifying process, reducing cell voltage, improving depositing rate, current efficiency and capacity, therefore exhibiting good development prospect. The issues that should be addressed in the future were also put forward and the connotation was expanded.
Key words: semiconductor element; illumination; cell voltage; photo-electrometallurgy; electrodeposition
