First principles studies on the redox ability of (Ga1−xZnx)N1−xOx solid solutions and thermal reactions for H2 and O2 production on their surfaces

文献情報

出版日 2013-09-27

DOI 10.1039/C3CP53091D

インパクトファクター 3.676

著者

Yaojun A. Du, Yun-Wen Chen, Jer-Lai Kuo

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要旨

The (Ga1−xZnx)N1−xOx solid solution has been emerging as an effective photocatalyst for water splitting utilizing the visible solar spectrum, regarded as a host GaN bulk doped with ZnO impurities. H2 and O2 production occur simultaneously and stoichiometrically on the surface of (Ga1−xZnx)N1−xOx particles. In this work, we characterize the redox ability of (Ga1−xZnx)N1−xOx and find that a solid solution with a ZnO concentration of 0.125 < x < 0.250 is optimal for water splitting. This is consistent with the experimental finding that the maximum photocatalytic activity of (Ga1−xZnx)N1−xOx is achieved at x = 0.13. The thermal reactions of water splitting are modeled on both the GaN and an idealized (Ga1−xZnx)N1−xOx (100) surface. The computed activation barriers allow us to gain some clues on the efficiency of water splitting on a specific photocatalyst surface. Our results suggest that the non-polar (100) and polar (0001) surfaces may play different roles in water splitting, i.e., the (100) surface is responsible for O2 production, while hydroxyl groups could dissociate on the (0001) surface.

掲載誌

Physical Chemistry Chemical Physics

CiteScore: 5.5

自己引用率: 10.3%

年間論文数: 3036

Physical Chemistry Chemical Physics (PCCP) is an international journal co-owned by 19 physical chemistry and physics societies from around the world. This journal publishes original, cutting-edge research in physical chemistry, chemical physics and biophysical chemistry. To be suitable for publication in PCCP, articles must include significant innovation and/or insight into physical chemistry; this is the most important criterion that reviewers and Editors will judge against when evaluating submissions. The journal has a broad scope and welcomes contributions spanning experiment, theory, computation and data science. Topical coverage includes spectroscopy, dynamics, kinetics, statistical mechanics, thermodynamics, electrochemistry, catalysis, surface science, quantum mechanics, quantum computing and machine learning. Interdisciplinary research areas such as polymers and soft matter, materials, nanoscience, energy, surfaces/interfaces, and biophysical chemistry are welcomed if they demonstrate significant innovation and/or insight into physical chemistry. Joined experimental/theoretical studies are particularly appreciated when complementary and based on up-to-date approaches.