title: Exceptional performance of photoelectrochemical water oxidation of single-crystal rutile TiO2 nanorods dependent on the hole trapping of modified chloride.
abstract: It is highly desired to effectively trap photogenerated holes for efficient photoelectrochemical (PEC) water oxidation to evolve O2 on oxide semiconductors. Herein, it is found for the first time mainly based on the time-resolved- and atmosphere-controlled- surface photovoltage responses that the modified chloride would effectively trap photogenerated holes so as to prolong the charge lifetime and hence promote charge separation of single-crystal rutile TiO2 nanorods. Its strong capacity to trap holes, comparable to the widely-used methanol and Co(II) phosphate, is well responsible for the exceptional photoactivities for PEC water oxidation to evolve O2 on rutile nanorods with a proper amount of chloride modified, about 2.5-time high as that on the resulting anatase nanoparticles, even 10-time if the surface area is considered. Moreover, it is suggested that the hole trapping role of chemically-adsorbed chloride is related to its lonely-pair electrons, and to the subsequently-produced intermediate Cl atoms with proper electronegativity for evolving O2. Interestingly, this finding is also applicable to the chloride-modified anatase TiO2. This work will provide a feasible strategy to design high-activity nanostructured semiconductor photoanodes for PEC water oxidation, even for overall water splitting.
authors.affiliation: Key Laboratory of Functional Inorganic Materials Chemistry (Heilongjiang University), Ministry of Education, National Center for International Research of Catalytic technology, School of Chemistry and Materials Science, Harbin 150080, P.R. China.
authors.forename: Xuliang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Functional Inorganic Materials Chemistry (Heilongjiang University), Ministry of Education, National Center for International Research of Catalytic technology, School of Chemistry and Materials Science, Harbin 150080, P.R. China.
authors.forename: Haiqin
authors.initials: H
authors.lastname: Cui
authors.affiliation: Key Laboratory of Functional Inorganic Materials Chemistry (Heilongjiang University), Ministry of Education, National Center for International Research of Catalytic technology, School of Chemistry and Materials Science, Harbin 150080, P.R. China.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Humayun
authors.affiliation: Key Laboratory of Functional Inorganic Materials Chemistry (Heilongjiang University), Ministry of Education, National Center for International Research of Catalytic technology, School of Chemistry and Materials Science, Harbin 150080, P.R. China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Qu
authors.affiliation: Key Laboratory of Functional Inorganic Materials Chemistry (Heilongjiang University), Ministry of Education, National Center for International Research of Catalytic technology, School of Chemistry and Materials Science, Harbin 150080, P.R. China.
authors.forename: Naiying
authors.initials: N
authors.lastname: Fan
authors.affiliation: Key Laboratory of Green Chemical Engineering and Technology of College of Heilongjiang Province, College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin 150040, P.R. China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Sun
authors.affiliation: Key Laboratory of Functional Inorganic Materials Chemistry (Heilongjiang University), Ministry of Education, National Center for International Research of Catalytic technology, School of Chemistry and Materials Science, Harbin 150080, P.R. China.
authors.forename: Liqiang
authors.initials: L
authors.lastname: Jing