In situ one-step hydrothermal synthesis of oxygen-containing groups-modified g-C3N4 for the improved photocatalytic H2-evolution performance

• Published in: Applied surface science Vol. 427; pp. 645 - 653
• Main Authors: Wu, Xinhe, Chen, Fengyun, Wang, Xuefei, Yu, Huogen
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.2018
• Subjects: g-C3N4; Hydrogen evolution photocatalyst; Hydrothermal treatment; Increased surface area; Modification; Oxygen functionalities; g-C3N4; Modification; Hydrothermal treatment; Hydrogen evolution photocatalyst; Increased surface area; Oxygen functionalities
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2017.08.050

[Display omitted] •An in situ one-step hydrothermal method was developed to prepare OG/g-C3N4.•Hydrothermal treatment greatly increase the specific surface area of bulk g-C3N4.•Hydrothermal treatment induce the formation of OH and CO on g-C3N4 surface.•The OG/g-C3N4 shows an obviously improved H2-evolution performance. Surface modification of g-C3N4 is one of the most effective strategies to boost its photocatalytic H2-evolution performance via promoting the interfacial catalytic reactions. In this study, an in situ one-step hydrothermal method was developed to prepare the oxygen-containing groups-modified g-C3N4 (OG/g-C3N4) by a facile and green hydrothermal treatment of bulk g-C3N4 in pure water without any additives. It was found that the hydrothermal treatment (180°C) not only could greatly increase the specific surface area (from 2.3 to 69.8m2g−1), but also caused the formation of oxygen-containing groups (OH and CO) on the OG/g-C3N4 surface, via the interlayer delamination and intralayer depolymerization of bulk g-C3N4. Photocatalytic experimental results indicated that after hydrothermal treatment, the resultant OG/g-C3N4 samples showed an obviously improved H2-evolution performance. Especially, when the hydrothermal time was 6h, the resultant OG/g-C3N4(6h) exhibited the highest photocatalytic activity, which was clearly higher than that of the bulk g-C3N4 by a factor of ca. 7. In addition to the higher specific surface area, the enhanced H2-evolution rate of OG/g-C3N4 photocatalysts can be mainly attributed to the formation of oxygen-containing groups, which possibly works as the effective H2-evolution active sites. Considering the facie and green synthesis method, the present work may provide a new insight for the development of highly efficient photocatalytic materials.