title: Phenylamine-Functionalized rGO/TiO2Photocatalysts: Spatially Separated Adsorption Sites and Tunable Photocatalytic Selectivity.
abstract: The preferential adsorption of targeted contaminants on a photocatalyst surface is highly required to realize its photocatalytic selective decomposition in a complex system. To realize the tunable preferential adsorption, altering the surface charge or polarity property of photocatalysts has widely been reported. However, it is quite difficult for a modified photocatalyst to realize the simultaneously preferential adsorption for both cationic and anionic dyes. In this study, to realize the selective adsorption for both cationic and anionic dyes on a photocatalyst surface, the negative reduced graphene oxide (rGO) nanosheets and positive phenylamine (PhNH2) molecules are successfully loaded on the TiO2surface (PhNH2/rGO-TiO2) with spatially separated adsorption sites, where the negative rGO and positive PhNH2molecules work as the preferential adsorption sites for cationic and anionic dyes, respectively. It was interesting to find that although all the TiO2samples (including the naked TiO2, PhNH2/TiO2, rGO-TiO2, and PhNH2/rGO-TiO2) clearly showed a better adsorption performance for cationic dyes than anionic dyes, only the PhNH2/rGO-TiO2with spatially separated adsorption-active sites exhibited an opposite photocatalytic selectivity, namely, the naked TiO2, PhNH2/TiO2, and rGO-TiO2showed a preferential decomposition for cationic dyes, while the resultant PhNH2/rGO-TiO2exhibited an excellently selective decomposition for anionic dyes. In addition, the resultant PhNH2/rGO-TiO2photocatalyst not only realizes the tunable photocatalytic selectivity but also can completely and sequentially decompose the opposite cationic and anionic dyes.
authors.affiliation: State Key Laboratory of Silicate Materials for Architectures, ‡School of Chemistry, Chemical Engineering and Life Sciences and §State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, P. R. China.
authors.forename: Huogen
authors.initials: H
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Silicate Materials for Architectures, ‡School of Chemistry, Chemical Engineering and Life Sciences and §State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, P. R. China.
authors.forename: Pian
authors.initials: P
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Silicate Materials for Architectures, ‡School of Chemistry, Chemical Engineering and Life Sciences and §State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, P. R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Tian
authors.affiliation: State Key Laboratory of Silicate Materials for Architectures, ‡School of Chemistry, Chemical Engineering and Life Sciences and §State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, P. R. China.
authors.forename: Fazhou
authors.initials: F
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Silicate Materials for Architectures, ‡School of Chemistry, Chemical Engineering and Life Sciences and §State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, P. R. China.
authors.forename: Jiaguo
authors.initials: J
authors.lastname: Yu
keywords: adsorption active sites; graphene; photocatalysis; photocatalytic selectivity; preferential adsorption