固态光电催化器件 ITO/TiO2/ITO 的构型和机制

 采用浸渍-提拉法将 TiO₂ 薄膜负载在具有一定电极构型的氧化铟锡 (ITO) 基底上, 制备了全固态 TiO₂ 平面型器件 (ITO/TiO₂/ITO). 采用扫描电镜对器件的表面形貌和膜厚进行了表征. 以紫外光下器件光电协同催化降解罗丹明 B(RhB) 为模型反应, 考察了器件的构型和空穴捕获剂 (乙醇) 对其光电催化性能的影响. 结果表明, 初始浓度为 10 mg/L 的 RhB 在 1.5 V 偏压和 NaCl (1.5 mol/L) 为电解质的条件下, 光照 60 min 脱色率达到 83%; 阳极面积较大的器件光电催化性能较好, 刻蚀宽度为 2 mm 时光电催化活性最高; 空穴与 TiO₂表面吸附的 H₂O 氧化生成的羟基自由基对液相光电催化降解 RhB 起着重要作用.

Configuration and Mechanism of Solid-State Photoelectrocatalytic Device ITO/TiO2/ITO

A solid-state TiO₂ planar device, ITO/TiO₂/ITO, was prepared by immobilizing TiO₂ film on indium-tin oxide (ITO) substrate with a certain electrode configuration through a dip-coating method. The surface morphology and film thickness of ITO/TiO₂/ITO were characterized by scanning electron microscopy. The effects of configurations of the device and hole scavenger (ethanol) on the photoelectrocatalytic synergetic degradation of rhodamine B (RhB) were investigated over the planar device ITO/TiO₂/ITO. The decoloration rate of RhB with the initial concentration of 10 mg/L reached 83% within 60 min. The ITO/TiO₂/ITO device with larger photoanode area presented better photoelectrocatalytic properties, and the device with the etching width of 2 mm exhibited the highest photoelectrocatalytic activity. The hydroxyl radicals produced by the water adsorbed on TiO₂ surface being oxidized by holes played an important role in liquid-phase photoelectrocatalytic degradation of RhB.