Novel Zn0.8Cd0.2S@g-C3N4 core–shell heterojunctions with a twin structure for enhanced visible-light-driven photocatalytic hydrogen generation

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2018, Vol.6 (35), p.17086-17094
• Main Authors: Feng-Yu, Tian, Hou, Dongfang, Tang, Fan, Deng, Min, Xiu-qing Qiao, Zhang, Qichun, Wu, Tao, Dong-Sheng, Li
• Format: Article
• Language: English
• Subjects: Carbon nitride; Energy conversion; Heterojunctions; Homojunctions; Hydrogen; Hydrogen production; Hydrogen-based energy; Irradiation; Light irradiation; Nanocomposites; Nanostructure; Photocatalysis; Radiation; Shell stability; Solid solutions
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c8ta05927f

A series of novel core–shell nanocomposites composed of twinned nanocrystal Zn0.8Cd0.2S solid solution and porous g-C3N4 nanosheets were fabricated by a combined ultrasonication and solvothermal method. The photocatalytic hydrogen production activities of these samples were evaluated without a co-catalyst in water under visible light irradiation (λ ≥ 420 nm). It is found that the H2 production rate of the Zn0.8Cd0.2S@g-C3N4-10 wt% sample was 2351.18 μmol h−1 g−1, which is 146.0 and 5.7 times higher than that of pristine porous g-C3N4 nanosheets and Zn0.8Cd0.2S solid solution. Further detailed characterization reveals that the drastically enhanced and stable light-to-hydrogen energy conversion can be attributed to not only the efficient spatial separation of the photo-induced electrons and holes resulted from the synergetic effects of twinned homojunctions and core–shell heterojunctions, but also the intimate contact at the molecular scale between the porous g-C3N4 shell and Zn0.8Cd0.2S core. Therefore, this work puts forward a promising way to obtain unique core–shell heterojunctions with excellent stability and activity during a photoreaction process.