(中南大學(xué) 化學(xué)化工學(xué)院 有色金屬資源化學(xué)教育部重點(diǎn)實(shí)驗(yàn)室，長沙 410083)
摘 要: 以偏鎢酸銨為鎢源、十六烷基三甲基溴化銨為表面活性劑，采用水熱法制備納米WO3粉體，并在不同溫度下進(jìn)行煅燒處理，通過添加分散劑、粘結(jié)劑等配制WO3漿料，利用刮涂法制備納米多孔WO3薄膜電極。通過TG-DTA、XRD、SEM、BET以及UV-vis吸收光譜等手段對樣品進(jìn)行表征，采用Mott-Schottky測試、穩(wěn)態(tài)光電流譜和交流阻抗譜等方法研究WO3 薄膜電極的光電化學(xué)性能。結(jié)果表明：所制備的WO3為單斜型，隨著熱處理溫度的升高，WO3粉體結(jié)晶度增高，顆粒粒徑增大，比表面積下降；將熱處理溫度為650 ℃的WO3粉體制得的薄膜呈多孔膨松狀結(jié)構(gòu)，其平帶電位為0.45 V，載流子濃度為3.445×1020 cm−3，光電流密度達(dá)2.50 mA/cm2。此外，進(jìn)一步探討顆粒尺寸對其光電性質(zhì)的影響及其機(jī)理。
關(guān)鍵字: WO3多孔薄膜；納米晶；粉末涂敷；光電化學(xué)
（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
