Deposition of nanoporous BiVO;thin-film photocatalyst by reactive magnetron sputtering: Effect of total pressure and substrate  

反应磁控溅射沉积纳米多孔BiVO4薄膜光催化剂:总压力和基底的影响

作　　者：Siavash BAKHTIARNIA Saeed SHEIBANI Alain BILLARD Eric AUBRY Mohammad ARAB POUR YAZDI 

机构地区：[1]School of Metallurgy and Materials Engineering,College of Engineering,University of Tehran,Tehran,Iran [2]Institut FEMTO-ST,UMR 6174,CNRS,Univ.Bourgogne Franche-Comté,15B,Avenue des Montboucons,25030 Besançon,France

出　　处：《Transactions of Nonferrous Metals Society of China》2022年第3期957-971,共15页中国有色金属学报（英文版）

基　　金：the supports of this study by the Iran National Science Foundation (No. 98001285);Pays de Montbéliard Agglomération (France) for the support of this work。

摘　　要：Nanoporous BiVO;thin films were deposited using reactive magnetron sputtering in Ar and O;atmosphere, on various substrates, employing pulsed direct-current(DC) power supplies applied to metallic Bi and V targets for rapid deposition. The procedure was followed by a post-annealing treatment in air to crystallize the photoactive monoclinic scheelite structure. The influence of total pressure and substrate on the crystal structure, morphology, microstructure, optical and photocatalytic properties of the films was investigated. The crystallization of monoclinic scheelite structure deposited on fused silica substrate starts at 250 ℃ and the films are stable up to 600 ℃. The morphology of the films is rather dense, despite at the high sputtering pressure(>2 Pa), with embedded nanopores. Among the thin films deposited on fused silica, the one deposited at 4.5 Pa exhibits the highest porosity(52%), with the lowest bandgap(2.44 eV) and it shows the highest photocatalytic activity in the degradation of Rhodamine-B(26% after 7 h) under visible light irradiation. The film deposited on the silicon substrate exhibits the highest photoactivity(53% after 7 h). Lack of hypsochromic shift in the UV-Vis temporal absorption spectra shows the dominance of the chromophore cleavage pathway in the photodecomposition.使用脉冲直流电源、金属Bi和V靶材,在氩气和氧气气氛保护下,通过反应磁控溅射法在不同基板上沉积纳米多孔BiVO;薄膜,然后在空气中进行后退火处理,形成具有光敏性的单斜白钨矿晶体。研究总压力和基底对薄膜晶体结构、形貌、显微组织、光学和光催化性能的影响。结果表明,在石英玻璃基底上沉积的单斜白钨矿结构于250℃开始结晶,薄膜在600℃时达到稳定。即使在较高的溅射压力(>2 Pa)下,薄膜的形貌也相当致密,且嵌有纳米孔。以石英玻璃为基体沉积的薄膜,在4.5 Pa条件下具有最高的孔隙率(52%),最低的能带隙(2.44 eV),且具有最高的在可见光照射下降解罗丹明-B的光催化活性(7h后为26%)。在硅基底上沉积的薄膜表现出最高的光活性(7 h后为53%)。薄膜在UV-Vis吸收光谱中缺乏蓝移,表明光解过程中以发色团裂解为主。

关 键 词：PHOTOCATALYSIS BIVO4 thin film SPUTTERING nanoporous film 

分 类 号：O643.36[理学—物理化学] O644.1[理学—化学]