Highly efficient two-electron electroreduction of oxygen into hydrogen peroxide over Cu-doped TiO2
Zhiqin Deng, Li Li, Yuchun Ren, Chaoqun Ma, Jie Liang, Kai Dong, Qian Liu, Yonglan Luo, Tingshuai Li, Bo Tang, Yang Liu, Shuyan Gao, Abdullah M. Asiri, Shihai Yan, Xuping Sun
Abstract
Electrosynthesis of hydrogen peroxide (H 2 O 2 ), as a sustainable alternative to the anthraquinone oxidation method, provides the feasibility of directly generating H 2 O 2 . Here, we report Cu-doped TiO 2 as an efficient electrocatalyst which exhibits the excellent two-electron oxygen reduction reaction (2e − ORR) performance with respect to the pristine TiO 2 . The Cu doping results in the distortion of TiO 2 lattice and further forms a large number of oxygen vacancies and Ti 3+ . Such Cu-doped TiO 2 exhibits a positive onset potential about 0.79 V and high H 2 O 2 selectivity about 91.2%. Moreover, it also shows a larger H 2 O 2 yield and good stability. Density functional theory (DFT) calculations reveal that Cu dopant not only improves the electrical conductivity of pristine TiO 2 but reduces the *OOH adsorption energy of active sites, which is beneficial to promote subsequently 2e − ORR process.