title: In situ preparation of a Ti³⁺ self-doped TiO₂ film with enhanced activity as photoanode by N₂H₄ reduction.
abstract: A new synthetic method to fabricate Ti(3+)-modified, highly stable TiO2 photoanodes for H2O oxidation is reported. With Ti foil as both the conducting substrate and the Ti(3+)/Ti(4+) source, one-dimensional blue Ti(3+)/TiO2 crystals were grown by a one-step hydrothermal reaction. The concentration of Ti(3+) was further tuned by N2H4 reduction, leading to a greater photoelectrocatalytic activity, as evidenced by a high photocurrent density of 0.64 mA cm(-2) at 1.0 V vs RHE under simulated AM 1.5 G illumination. Electron paramagnetic resonance and Mott-Schottky plots reveal that higher charge-carrier density owing to N2H4 reduction contributes to the observed improvement. The generality of this synthesis method was demonstrated by its effectiveness in improving the performance of other types of photoanodes. By integrating the advantages of the 1D TiO2 architecture with those of Ti(3+) self-doping, this work provides a versatile tool toward the fabrication of efficient TiO2 photoanodes.
authors.affiliation: Materials Science and Engineering Program, University of California, Riverside, CA 92521 (USA).
authors.forename: Chengyu
authors.initials: C
authors.lastname: Mao
authors.forename: Fan
authors.initials: F
authors.lastname: Zuo
authors.forename: Yang
authors.initials: Y
authors.lastname: Hou
authors.forename: Xianhui
authors.initials: X
authors.lastname: Bu
authors.forename: Pingyun
authors.initials: P
authors.lastname: Feng
keywords: photoanodes; self-doped TiO2; titanium; water oxidation