Li, X.Zhang, H.Liu, Y.Duan, X.Xu, X.Liu, S.Sun, H.Wang, S.2020-07-062020-07-062020Chemical Engineering Journal, 2020; 390:124634-1-124634-91385-89471873-3212http://hdl.handle.net/2440/126376Solar-to-hydrogen holds a great sustainable energy solution, in which photocatalysis plays an important role. In this study, a composite photocatalyst with NiO quantum dots (NiO QDs) in graphitic carbon nitride (g-CN) was synthesized and evaluated in photocatalytic (PC) and thermophotocatalytic hydrogen evolution reaction (HER) under visible light. A sample of 9 wt% NiO QDs-g-CN achieved the highest PC-HER rate of 130 μmol·g−1·h−1 at ambient condition, 11 times higher than pristine g-CN. Meanwhile the thermophotocatalytic HER rate reached 260.2 μmol·g−1·h−1 at 55 °C. Photo-illumination led to the formation of CO bond between g-CN and NiO QDs to bridge photoelectron transport for low HER overpotential barriers and enhanced electrical conductivity. The higher thermophoto-induced HER can be ascribed to the increased electrical conductivity of NiO QDs-g-CN. This work underlines the importance of chemical binding in hetero-structures and quantum confinement effects in QDs-based composites, and it also demonstrates the thermal sensitivity effect in thermophotocatalytic HER process.en© 2020 Elsevier B.V. All rights reserved.Quantum dots; graphitic carbon nitride; photocatalysis; thermophotolysis; hydrogen productionJournal article100001785310.1016/j.cej.2020.1246340005226401001252-s2.0-85081005032526113Duan, X. [0000-0001-9635-5807]Wang, S. [0000-0002-1751-9162]