(中南大學(xué) 冶金與環(huán)境學(xué)院，長(zhǎng)沙410083)
摘 要: 針對(duì)電化學(xué)冶金提取半導(dǎo)體元素存在的問題，提出采用光電化學(xué)冶金的方法來進(jìn)行半導(dǎo)體元素的電化學(xué)沉積提取。結(jié)合半導(dǎo)體特性以及光電化學(xué)基本理論，闡述光電化學(xué)冶金的優(yōu)勢(shì)，并以碲提取為例驗(yàn)證光電化學(xué)冶金的優(yōu)越性。結(jié)果表明：光電化學(xué)沉積過程中，半導(dǎo)體沉積物吸收能量大于其自身帶隙寬度的光子后受激發(fā)產(chǎn)生光生電子-空穴對(duì)，光生電子從半導(dǎo)體流向電解液促進(jìn)電化學(xué)還原，同時(shí)光生載流子可減小電阻率和能帶彎曲，降低工作電極所分?jǐn)偟碾妱?shì)差。與常規(guī)的電化學(xué)沉積相比，光電化學(xué)沉積可以強(qiáng)化電極過程、降低槽電壓，以及提高沉積速率、電流效率和產(chǎn)能，具有良好的應(yīng)用前景。最后指出光電化學(xué)冶金未來發(fā)展可能面臨的問題，并對(duì)其內(nèi)涵進(jìn)行拓展。
關(guān)鍵字: 半導(dǎo)體元素；光照；槽電壓；光電化學(xué)冶金；電化學(xué)沉積
（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
