Novel Zn_0.8Cd_0.2S@g-C₃N₄core–shell heterojunctions with a twin structure for enhanced visible-light-driven photocatalytic hydrogen generation

Feng-Yu Tian, Dongfang Hou, Fan Tang, Min Deng, Xiu-qing Qiao, Qichun Zhang, Tao Wu and Dong-Sheng Li

A series of novel core–shell nanocomposites composed of twinned nanocrystal Zn_0.8Cd_0.2S solid solution and porous g-C₃N₄nanosheets 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 H₂production rate of the Zn_0.8Cd_0.2S@g-C₃N₄-10 wt% sample was 2351.18 μmol h⁻¹g⁻¹, which is 146.0 and 5.7 times higher than that of pristine porous g-C₃N₄nanosheets and Zn_0.8Cd_0.2S 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-C₃N₄shell and Zn_0.8Cd_0.2S core. Therefore, this work puts forward a promising way to obtain unique core–shell heterojunctions with excellent stability and activity during a photoreaction process.

文章链接：http://pubs.rsc.org/en/content/articlelanding/2018/ta/c8ta05927f#!divAbstract