马来酸在束状TiO2阳极氧化膜上的电催化还原

采用阳极氧化法在0.5 mol·L-1硫酸+1 mol·L-1马来酸的混合溶液中制得了束状TiO2薄膜. X射线衍射(XRD)分析表明样品的晶型结构主要为无定形态; 所制得的样品通过原子力显微镜(AFM)观察, 束状结构TiO2的宽度约2-5 μm, 长度超过20 μm, 束状结构中包含的纳米棒直径约80-150 nm. 将制得的束状TiO2膜电极在上述混合溶液中直接进行原位的循环伏安扫描和恒电流电解实验. 研究结果表明, 马来酸在该电极表面异相电催化还原生成丁二酸; 在恒电流电解过程中采用电极原位活化可明显提高丁二酸的产率和电流效率, 并指出改进电极的原位活化技术是未来研究工作的主要目标.

Electrocatalytic Reduction of Maleic Acid at Bundles of TiO2 Anodization Film

Anodic oxidation is a novel and simple method to fabricate TiO2 film with particular morphologies in a mixture of 0.5 mol·L-1 H2SO4+1 mol·L-1 maleic acid solution. The formation of a mixture containing low crystal rutile phase and amorphous structure of TiO2 was confirmed by X-ray diffraction (XRD). Bundle structures of TiO2 film with the breadth of 2-5 μm and the length over 20 μm were observed by atomic force microscope (AFM). Simultaneously, we found that the average diameter of the fine stick within the bundle structures of TiO2 was 80-150 nm. Electrocatalytic reduction of maleic acid to succinic acid was investigated by cyclic voltammetry and galvanostatic electrolysis experiments. The heterogeneous catalytic reduction of maleic acid could be confirmed with a comparison of the cyclic voltammetry recorded in the absence and the presence of maleic acid on the bunchy TiO2 film surface. In-situ activation of the as-anodized TiO2 electrode by galvanic cycle for galvanostatic electrolysis experiments brought the maximum yield of succinic acid and current efficiency.