Synthesis of a-SnWO_4 thin-film electrodes by hydrothermal conversion from crystalline WO_3

作     者：Kayla J.Pyper Taylor C.Evans Bart M.Bartlett 

作者机构：Department of Chemistry University of Michigan 

出 版 物：《Chinese Chemical Letters》 (中国化学快报（英文版）)

年 卷 期：2015年第26卷第4期

页      面：474-478页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 070205[理学-凝聚态物理] 08[工学] 0817[工学-化学工程与技术] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported by a grant from a National Science Foundation (No.DMR-1253347) 

主　　题：Alpha tin tungstateHydrothermal conversionMicrostructureHydrothermal method 

摘      要：Thin film electrodes of the orthorhombic form of tin tungstate （α-SnWO4） were prepared using a hydrothermal method to convert thin films of WO3 in aqueous SnCI2. The pH dependence of the growth mechanism was identified by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The XRD patterns show complete conversion of WO3（s） to SnWO4（s） at pH 1, 4, and 7. SEM images reveal a morphology change from sponge-like platelets to sharp nanowires as the pH increases from 1 to 7. The α-SnWO4 thin films were reddish brown in color, and display an indirect band gap of 1.9 eV by diffuse reflectance UV-vis spectroscopy. α-SnWO4 is therefore solar-responsive, and a chopped light linear sweep voltammogram recorded under 100 mW/cm2 AM1.5 simulated solar illumination in a pH 5 0.1 mol/L KPi buffer show a visible light response for photoelectrochemical water oxidation, producing 32 μA/cm2 at 1.23 V vs. RHE.