(中南大学 化学化工学院 有色金属资源化学教育部重点实验室，长沙 410083)
摘 要: 以偏钨酸铵为钨源、十六烷基三甲基溴化铵为表面活性剂，采用水热法制备纳米WO3粉体，并在不同温度下进行煅烧处理，通过添加分散剂、粘结剂等配制WO3浆料，利用刮涂法制备纳米多孔WO3薄膜电极。通过TG-DTA、XRD、SEM、BET以及UV-vis吸收光谱等手段对样品进行表征，采用Mott-Schottky测试、稳态光电流谱和交流阻抗谱等方法研究WO3 薄膜电极的光电化学性能。结果表明：所制备的WO3为单斜型，随着热处理温度的升高，WO3粉体结晶度增高，颗粒粒径增大，比表面积下降；将热处理温度为650 ℃的WO3粉体制得的薄膜呈多孔膨松状结构，其平带电位为0.45 V，载流子浓度为3.445×1020 cm−3，光电流密度达2.50 mA/cm2。此外，进一步探讨颗粒尺寸对其光电性质的影响及其机理。
关键字: WO3多孔薄膜；纳米晶；粉末涂敷；光电化学
（Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education,
School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China）
Abstract:Tungsten trioxide nanoparticles were synthesized by a hydrothermal method using ammonium metatungstate as tungsten source and cetyl-trimethyl ammonium bromide as surfactant with subsequent calcination treatment at different temperatures. The as-prepared WO3 nanoparticles were mixed with dispersing agent and binder to obtain WO3 paste, which was then coated on FTO substrate to fabricate nanocrystalline porous WO3 films by the doctor-blade method. The obtained materials were characterized by means of TG-DTA, XRD, SEM, BET and UV-vis absorption. The photoelectrochemical properties of the WO3 film electrodes were investigated by Mott-Schottky, photocurrent-potential curve and electrochemical impedance spectroscopy (EIS) analysis. The results indicate that the films are crystalline with a monoclinic and porous structure, and the size of WO3 increases at elevated calcination temperature. The sample prepared using WO3 powders calcined at 650 ℃ shows that the flat band potential, donor carrier density, and photocurrent density are 0.46 V, 3.445×1020 cm−3 and 2.50 mA/cm2, respectively. The effect of different particle sizes on the photoelectrochemical properties of the WO3 films was also investigated.
Key words: WO3 porous films; nanocrystalline; power-coating; photoelectrochemistry
