研究了碳量子点负载的TiO2纳米棒阵列光阳极的光电化学过程和光催化行为。实验发现碳量子点的引入使TiO2纳米棒阵列在可见光区域的吸收强度增强,对可见光的响应电流提高3倍,光照下的开路电位增加了2.5%,光生载流子的转移和传输能力得到相应提高。光阳极对亚甲基蓝的降解特性显示,碳量子点的引入使TiO2纳米棒在可见光照射下的催化效率由25%提高到33%。利用电化学交流阻抗谱(EIS)、Mott-Schottky曲线讨论了光影响下的电荷运动过程,表明TiO2纳米棒阵列负载碳量子点后的电荷转移电阻减小,电子寿命增加; 碳量子点的负载使TiO2纳米棒的平带电位负移,导带位置提高,电子的还原能力增强。

The photoelectrochemical (PEC) performance and photocatalytic activity of TiO2 nanorod arrays (NRs) loaded with carbon quantum dots (CQDs) were investigated. In comparison with TiO2 NRs, the absorption ability of TiO2 NRs loaded with CQDs was enhanced. The transient photocurrent and open-circuit potential under visible light illumination were increased of 300% and 2.5%, respectively. After loaded with CQDs, the photocatalytic degradation efficiency of methylene blue (MB) under visible light illumination was increased from 25% to 33%. The electrochemical impedance spectra (EIS) and Mott-Schottky plots were measured to investigate the charge movement under the visible light illumination. The results suggest that the charge transfer resistance is reduced and the electron lifetime is increased for TiO2 NRs loaded with CQDs. The loading of CQDs can induce the flat-band potential negative shift and the conduction band position raise, resulting in the enhancement of electron reduction properties.