title: Influence of TiO2hollow sphere size on its photo-reduction activity for toxic Cr(VI) removal.
abstract: After polystyrene@titanium dioxide (PS@TiO2) composite with different size was calcined at designated temperature, TiO2hollow sphere with controllable size was obtained for high efficient photo-reduction of Cr(VI). The feature of the TiO2hollow sphere was investigated by SEM, TEM, XRD, UV-Vis, and photoluminescence. The photo-reduction of Cr(VI) were measured for the performance assessment of the TiO2hollow sphere, Cr(VI) was used as an electron acceptor. After irradiation for 2h, the photo-reduction rate of Cr(VI) (pH=2.82) for TiO2(450nm) was 96%, which exhibited an increase of 5% and 8% compared with TiO2(370nm) and TiO2(600nm). The absorption edges of TiO2hollow sphere (450nm) was largest with the increasing of hollow sphere size from 370 to 600nm. The optimal hollow sphere size of TiO2was 450nm for the photo-reduction of Cr(VI), because the light-harvesting efficiency (the best of absorption edge) and photo-generated electron-hole separation rate (the best of photo-reduction rate) of TiO2hollow sphere were controlled by its hollow sphere size. In addition, we find that the behavior of the hydrogen production was inhibited by the coexistence Cr(VI) solution. This study can improve our understanding of the mechanism for the activity enhancement by the optimal hollow sphere size of TiO2.
authors.affiliation: College of the Environment and Ecology, Xiamen University, Xiamen 361102, PR China; College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Jiabai
authors.initials: J
authors.lastname: Cai
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Xueqing
authors.initials: X
authors.lastname: Wu
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China; Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Fengying
authors.initials: F
authors.lastname: Zheng
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China; Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou 363000, PR China. Electronic address: shunxing_li@aliyun.com.
authors.forename: Shunxing
authors.initials: S
authors.lastname: Li
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Yaling
authors.initials: Y
authors.lastname: Wu
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Lin
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Liting
authors.initials: L
authors.lastname: Lin
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Biwen
authors.initials: B
authors.lastname: Liu
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Qiaoying
authors.initials: Q
authors.lastname: Chen
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Luxiu
authors.initials: L
authors.lastname: Lin
keywords: Controllable size; Cr(VI); Hollow sphere; Photo-reduction; TiO(2)