title: Au@Cu2O stellated polytope with core-shelled nanostructure for high-performance adsorption and visible-light-driven photodegradation of cationic and anionic dyes.
abstract: Au nanoparticles were covered by Cu2O nanoparticles shell and then Au@Cu2O stellated polytope was synthesized by a facile aqueous solution approach. The samples were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction patterns, X-ray photoelectron spectroscopy, Brunner-Emmet-Teller measurements, and Ultraviolet-visible spectroscopy analysis. With good aqueous dispersibility, surface positive charge, and high chemisorption capacity, Au@Cu2O could be used for anionic dyes removal. Compared with Degussa P25-TiO2, the adsorption of anionic dyes (acid violet 43 or methyl blue, 5.0 mg L(-1)) onto Au@Cu2O was increased by 90.12% and 50.8%, respectively. The photodegradation activity of methyl orange and methyl violet were in the declining order: Au@Cu2O>Cu2O-Au nanocomposites>Cu2O>P25-TiO2. The synergistic effect of coupling Au core with Cu2O shell on the dyes photodegradation was observed. The photoexcited electrons from Cu2O conduction band could be captured by Au nanoparticles, resulting in an improved electron-hole separation. Moreover, a Schottky barrier was assumed to form at the Cu2O-Au interface and Au NPs as electron sink could reduce the recombination of photoinduced electrons and holes, facilitating the photocatalytic interface reaction. The geometry of core-shell and stellated polytope is effective in the design of Cu2O-Au nanocomposites for adsorption and photocatalysis.
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; College of the Environment & Ecology, Xiamen University, Xiamen 361005, 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; 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; 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.
authors.forename: Zhanghua
authors.initials: Z
authors.lastname: Lai
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Licong
authors.initials: L
authors.lastname: Zhu
authors.affiliation: College of Chemistry and Environment, Minnan Normal University, Zhangzhou 363000, PR China.
authors.forename: Tanju
authors.initials: T
authors.lastname: Chen
keywords: Core–shell nanomaterials; Photodegradation; Stellated polytope; Sunlight