title: Carbon coating stabilized Ti(3+)-doped TiO2 for photocatalytic hydrogen generation under visible light irradiation.
abstract: Self-doping by Ti(3+) is a useful method to expand the light response of TiO2 into the visible light region. However, to obtain a stable Ti(3+)-doped TiO2 seems to be a challenge due to the easy oxidation of Ti(3+) during the heterogeneous reaction. Here, we propose a simple carbon coating route to stabilize the Ti(3+)-doped TiO2, in which both the Ti(3+) and precursor of the carbon coating layer were in situ formed from the hydrothermal hydrolysis of titanium isopropoxide. The carbon coated Ti(3+)-doped TiO2 exhibited excellent stability for photocatalytic hydrogen production. Based on electron paramagnetic resonance (EPR) analysis, the proposed stabilizing mechanism is that the conductive carbon coating layer as a barrier layer prevents the H2O and O2 from diffusing into the surface of the photocatalyst, which can oxidize the surface O vacancies and Ti(3+) in TiO2. Our findings offer a simple route to prepare a highly stable TiO2-based photocatalyst with visible light response.
authors.affiliation: National Laboratory of Solid State Microstructures & Ecomaterials and Renewable Energy Research Center (ERERC) at Department of Physics, Nanjing University, Nanjing 210093, P. R. China. yutao@nju.edu.cn.
authors.forename: Gao
authors.initials: G
authors.lastname: Fu
authors.forename: Peng
authors.initials: P
authors.lastname: Zhou
authors.forename: Meiming
authors.initials: M
authors.lastname: Zhao
authors.forename: Weidong
authors.initials: W
authors.lastname: Zhu
authors.forename: Shicheng
authors.initials: S
authors.lastname: Yan
authors.forename: Tao
authors.initials: T
authors.lastname: Yu
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zou