title: A critical study of the generality of the two step two electron pathway for water splitting by application of a C3N4/MnO2 photocatalyst.
abstract: A novel C3N4-CDot composite photocatalyst was very recently shown to be highly efficient and very stable in water splitting by solar radiation without using any sacrificial reagent (J. Liu, et al., Science, 2015, 347(6225), 970). This photocatalyst utilizes a two-electron/two-step process in which the production of H2O2 and H2 is photocatalyzed by using C3N4 in the first step and H2O2 is decomposed by using CDots in the second step. The present work is a study on the generality of this approach by application of a C3N4/MnO2 catalyst. This new catalyst indeed splits water by a two step process in a stable way, without any sacrificial agent. It was however found that though the absorbance of the new catalyst in the visible range of 500-600 nm is much larger than that of the C3N4-CDot catalyst, its water splitting efficiency is much lower. These findings add insight into and assist in the further optimization of this new class of photocatalysts to meet the requirements of commercial water splitting systems.
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: N Y
authors.initials: NY
authors.lastname: Liu
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: H
authors.initials: H
authors.lastname: Li
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: L P
authors.initials: LP
authors.lastname: Wang
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: X Q
authors.initials: XQ
authors.lastname: Wu
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: H
authors.initials: H
authors.lastname: Huang
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: F
authors.initials: F
authors.lastname: Bao
authors.affiliation: Department of Materials Science and Engineering, Technion, Israel Institute of Technology, Haifa, Israel. shayli@technion.ac.il.
authors.forename: Y
authors.initials: Y
authors.lastname: Lifshitz
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: S-T
authors.initials: ST
authors.lastname: Lee
authors.affiliation: Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, China. zhkang@suda.edu.cn yangl@suda.edu.cn.
authors.forename: Z H
authors.initials: ZH
authors.lastname: Kang