Electrodeposited Amorphous Iron(Ⅲ) Oxides as Anodes for Photoelectrolysis of Water

電化學沉積非結晶性的三價鐵氧化物作為光分解水的陽極電極

李佩珊(Pei-Shan Li) ； 鄧熙聖(Hsi-Sheng Teng)

《Journal of the Chinese Institute of Chemical Engineers》 38卷3&4期 (2007/07) Pp. 267-273

摘要

在0.1M的硫酸亞鐵銨溶液((NH4)2Fe(SO4)2•6H2O)中，藉由施加-1.6V(V vs. Ag/AgCl)的陰極偏壓可在導電玻璃上沉積非結果性的三價鐵氧化物膜。X光近緣結構(X-ray Absorption Near-Edge Structure)確定此非結晶性膜具有三價鐵的特徵。在光電化學中，施加正偏壓産生的光電流應答，可看出沉積膜具有n型半導體的特性。利用Mott-Schottky原理及循環伏安法(Cyclic Voltammetry)可鑑定出沈積膜的半導體特性，包括有能帶差(2.2eV)、載子濃度(1×10^22cm^(-3))、導帶、價帶以及平帶位置（依序為-0.6V、+1.6V和-0.58V vs. Ag/AgCl於pH7）。此非結晶性的沈積膜適合做為光分解水的陽極電極。

並列摘要

Deposition of amorphous iron(Ⅲ)-oxide films on a conducting glass substrate was achieved via a cathodic bias in a 0.1 M hydrated ammonium iron(Ⅲ) sulfate ((NH4)2Fe(SO4)2•6H2O) solution at -1.6V versus Ag/AgCl. Analysis by X-ray absorption near edge structure confirmed the iron(Ⅲ) feature of the amorphous films. The deposited films exhibited n-type semiconducting characteristics by showing photoresponses under an anodic bias. The Mott-Schottky method and cyclic voltammetry were employed to characterize the semiconducting properties of the deposited Ag/AgCl at pH 7, respectively), and the donor density (1×10^22/cm^3). The deposited iron(Ⅲ)-oxide films were suitable to serve as an anode for water splitting under illumination.

並列關鍵字

Iron Ⅲ oxide ； Photoelectrolysis ； Water splitting ； Semiconducting properties ； Photoelectrode