TiO_2光电化学电池催化氧化甲基红

以钛基TiO2薄膜为光阳极,研究了光电化学电池中阳极光催化降解偶氮染料甲基红的动力学.结果表明,短接光电化学电池分隔了光催化过程的阴、阳极反应,有利于抑制光生载流子的复合,提高光催化氧化速率.相同实验条件下短路光电流越大,则甲基红降解速率越高.在基底和TiO2薄膜之间夹层SnO2得到组装电极Ti/SnO2/TiO2,进一步提高了光生载流子的分离效率;同时采用电化学阻抗谱(EIS)评价了电极的光催化性能.

Photocatalytic Oxidation of Methyl Red by TiO_2 in a Photoelectrochemical Cell

The kinetics for photocatalytic degradation reaction of methyl red, an azo dye, was investigated in a photoelectrochemical(PEC) cell, with titania thin film loaded on titanium as photoanode. The results showed that the degradation of methyl red was accelerated in PEC cell due to a reduced recombination of photogenerated carriers by the separation of the anodic and cathodic reactions. Under the same condition, an increase in photocurrent for PEC cell will suggest an improved rate of degradation. A thin SnO2 film was applied as an interlayer between the substrate and the TiO2 coating to obtain the assembled photoanodes, Ti/SnO2/TiO2, leading to a more separation efficiency of photogenerated carriers. Meanwhile, the photocatalytic activities of the electrodes were estimated by the electrochemical impedance spectroscopy (EIS).