Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Phys Chem Chem Phys. 2014 Jan 28;16(4):1327-32. doi: 10.1039/c3cp53324g.
The physical and photoelectrochemical properties of a composite oxide photoelectrode comprised of α-Fe2O3 and WO3 crystals is investigated. The composite films exhibit a water oxidation photocurrent onset potential as low as 0.43 V vs. RHE, a value considerably lower than that of pure α-Fe2O3 photoanodes prepared in comparable synthesis conditions. This result represents one of the lowest onset potentials measured for hematite-based PEC water oxidation systems. Compositional analysis by X-ray Photoelectron Spectroscopy and Energy Dispersive Spectroscopy indicates the composition of the films differs between the surfaces and bulk, with tungsten found to be concentrated in the surface region. Post-reaction Raman spectroscopy characterization demonstrates that water interacts with surface WO3 crystals, an event that is associated with the formation of a hydrated form of the oxide.
研究了由α-Fe2O3 和 WO3 晶体组成的复合氧化物光电化学电极的物理和光电化学性质。复合薄膜表现出的水氧化光电流起始电位低至 0.43 V vs. RHE，这一数值明显低于在可比合成条件下制备的纯α-Fe2O3 光阳极。这一结果是在基于赤铁矿的 PEC 水氧化体系中测量到的最低起始电位之一。X 射线光电子能谱和能量色散光谱的组成分析表明，薄膜的组成在表面和体相之间存在差异，钨集中在表面区域。反应后拉曼光谱表征表明，水与表面 WO3 晶体相互作用，这一事件与氧化物的水合形式的形成有关。
