title: Design and simple synthesis of composite Bi12TiO20/Bi4Ti3O12with a good photocatalytic quantum efficiency and high production of photo-generated hydroxyl radicals.
abstract: Hybrid Bi12TiO20/Bi4Ti3O12composites with different Bi : Ti molar ratios were successfully fabricated using a one-step solid-state calcination. These samples were characterized using X-ray diffraction, specific surface area analysis, scanning electron microscopy, high-resolution microscopy, selected-area electron diffraction, X-ray photoelectron spectroscopy, UV-vis diffuse reflection spectroscopy, photoluminescence analyses, and photocurrent and electrochemical impedance spectroscopy. Some specified techniques were also used to investigate the photocatalytic properties and the formation of radical species under UV-vis irradiation. The composites provide an efficient pathway for photo-produced electrons and holes to diffuse and transfer to the exterior of the particles for photodegradation, because of the good contact between hybrid Bi12TiO20and Bi4Ti3O12. Therefore, the hybrid Bi12TiO20/Bi4Ti3O12can prolong the carrier lifetime as compared to any individual material (Bi12TiO20or Bi4Ti3O12). In particular, the hybrid Bi12TiO20/Bi4Ti3O12composite with a Bi : Ti ratio of 12 : 6 had the longest photo-generated carrier lifetime and produced the maximum amount of hydroxyl radicals during UV-vis irradiation; therefore, it demonstrated the best photo-catalytic properties. A Z-scheme mechanism was proposed to explain the hydroxyl radical yield and photodegradation.
authors.affiliation: Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and Institute for Advanced Materials, School of Physics and Telecommunication of South China Normal University, Guangzhou 510006, People's Republic of China. mostlucky1314@163.com.
authors.forename: Chun
authors.initials: C
authors.lastname: Du
authors.affiliation: Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and Institute for Advanced Materials, School of Physics and Telecommunication of South China Normal University, Guangzhou 510006, People's Republic of China. mostlucky1314@163.com.
authors.forename: Donghai
authors.initials: D
authors.lastname: Li
authors.affiliation: Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and Institute for Advanced Materials, School of Physics and Telecommunication of South China Normal University, Guangzhou 510006, People's Republic of China. mostlucky1314@163.com.
authors.forename: Qinyu
authors.initials: Q
authors.lastname: He
authors.affiliation: Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and Institute for Advanced Materials, School of Physics and Telecommunication of South China Normal University, Guangzhou 510006, People's Republic of China. mostlucky1314@163.com.
authors.forename: Junming
authors.initials: J
authors.lastname: Liu
authors.affiliation: Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and Institute for Advanced Materials, School of Physics and Telecommunication of South China Normal University, Guangzhou 510006, People's Republic of China. mostlucky1314@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and Institute for Advanced Materials, School of Physics and Telecommunication of South China Normal University, Guangzhou 510006, People's Republic of China. mostlucky1314@163.com.
authors.forename: Guannan
authors.initials: G
authors.lastname: He
authors.affiliation: Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and Institute for Advanced Materials, School of Physics and Telecommunication of South China Normal University, Guangzhou 510006, People's Republic of China. mostlucky1314@163.com.
authors.forename: Yinzhen
authors.initials: Y
authors.lastname: Wang