选择泡沫钛片和普通钛片,通过溶胶凝胶法、阳极氧化法和脉冲式超声辅助阳极氧化法制备了5种不同的电极作为光催化燃料电池阳极.结果表明,不同方法制备的电极表面结构有所不同,其光阳极电极电位与有机物降解性能也不同.泡沫钛基溶胶凝胶法和超声辅助阳极氧化法制备的电极表面更加粗糙,比表面积也更大,加强了有机物的传质,有利于有机物的迁移与空穴氧化反应及敏化反应.超声辅助阳极氧化方法制备的电极对罗丹明B模拟废水的脱色率最高,p H=1时,120 min内达80%.电极电位的测定结果还表明,两种粗糙电极光激发电极电位比同种方法制备的其它电极高约0.15 V,光照前后的阳极半反应电位差更小,激发电子的积累也较少.这些研究结果对光催化燃料电池的电极选择与电池构建具有参考作用.
In this paper,we found that TiO_2 anodes with different surface morphologies showed different organic degradation performances and,more importantly,different anodic potentials. Five photoanodes with different morphologies were fabricated by sol-gel,anodic oxidation and pulsed ultrasonic wave-assisted anodic oxidation method respectively. The foam titanium based TiO_2 elecrode made by sol-gel and the titanium based electrode made by ultrasonic-assisted anodic oxidation had a rougher surface and therefore a larger specific surface area which is beneficial to organics oxidation by photo-excited holes and dye sensitization. Mass transfer of organic substances was also enhanced.The electrode prepared by ultrasonic-assisted anodic oxidation had the best performance in Rhodamine B degradation,with a decolourization rate of 80% in 120 min at p H = 1. Furthermore,two rough electrodes had 0. 15 V higher photo-excited anodic potential and a smaller shift of the potential with and without illumination compared with other electrodes,indicating less accumulation of photo-excited electrons on the photoanodes. These results help gain insight into the significance of photoanode morphology and PFC construction.