Zhang Yuanwen, Xu Jingsan, Mei Jun, Sarina Sarina, Wu Ziyang, Liao Ting, Yan Cheng, Sun Ziqi
School of Chemistry and Physics, Queensland University of Technology, QLD, 4000, Australia.
School of Chemistry and Physics, Queensland University of Technology, QLD, 4000, Australia; School of Mechanical, Medical and Process Engineering, Queensland University of Technology, QLD, 4000, Australia.
J Hazard Mater. 2020 Jul 15;394:122529. doi: 10.1016/j.jhazmat.2020.122529. Epub 2020 Mar 12.
Two-dimensional (2D) nanosheet-based nanocomposites have attracted intensive interest owing to the unique electronic and optical properties from their constituent phases and the synergistic effect from the heterojunctions. In this study, an interfacial coupled TiO/g-CN 2D-2D heterostructure has been prepared via in situ growth of ultrathin 2D-TiO on dispersed g-CN nanosheets. This strongly coupled 2D-2D TiO/g-CN, different from the weakly bonded 2D-TiO/g-CN heterostructures produced by mechanical mixing, has unique electronic structures and chemical states due to strong interlayer charge transfer, confirmed by both experimental and theoretical analyses. Significantly enhanced visible-light responses have been observed, indicating a great potential for visible-light induced photosynthesis and photocatalysis. For benzylamine coupling reactions under visible-light irradiation, 80 % yield rate has been achieved, superior to ∼30 % yield rate when adopting either 2D-TiO or g-CN structure. The enhanced photocatalytic activity can be attributed to the adequate separation of photo-generated electrons at the strongly coupled 2D-2D heterojunction interfaces.
基于二维（2D）纳米片的纳米复合材料因其组成相独特的电子和光学性质以及异质结的协同效应而引起了广泛关注。在本研究中，通过在分散的g-CN纳米片上原位生长超薄二维TiO制备了一种界面耦合的TiO/g-CN二维-二维异质结构。这种强耦合的二维-二维TiO/g-CN与机械混合产生的弱键合二维TiO/g-CN异质结构不同，由于层间电荷转移强烈，具有独特的电子结构和化学状态，这已通过实验和理论分析得到证实。观察到可见光响应显著增强，表明在可见光诱导的光合作用和光催化方面具有巨大潜力。对于可见光照射下的苄胺偶联反应，产率达到了80%，优于采用二维TiO或g-CN结构时约30%的产率。光催化活性的增强可归因于在强耦合的二维-二维异质结界面处光生电子的充分分离。
