Wang Xin, Ma Jing, Fan Jianhua, Zhu Hui, Liu Xingman, Xia Hongqiang, Liu Yingtao
State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, National Demonstration Center for Experimental Chemistry Education, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China.
J Chem Inf Model. 2023 Aug 14;63(15):4708-4715. doi: 10.1021/acs.jcim.3c01089. Epub 2023 Aug 3.
The charge transfer mechanism of the g-CN/MoS heterojunction is still disputed. Some regard it as a type I pathway, some regard it as a type II pathway, and still some regard it as a Z-scheme pathway. Especially, the results obtained by density functional theory (DFT) calculations are not totally in agreement. Here, we constructed four g-CN/MoS heterojunctions on the basis of the aperture alignment modes of g-CN and MoS. Their morphology and photocatalytic activity were investigated via first-principles and excited state dynamics simulations. By systemically comparing the interfacial binding energy and electronic structure (e.g., band structure, electrostatic potential, and band edge positions) of g-CN/MoS heterojunctions, we found that both type I and type II band alignment structures could be obtained. Moreover, the calculated lifetimes of interlayer photogenerated electrons and holes show that type II g-CN/MoS tends to favor a general type II pathway rather than a Z-scheme pathway. This study could provide a deep understanding of the photocatalytic mechanism of g-CN/MoS van der Waals heterostructures, which will be of great use for applications in photocatalysis.
g-CN/MoS异质结的电荷转移机制仍存在争议。一些人认为它是I型途径，一些人认为它是II型途径，还有一些人认为它是Z型途径。特别是，密度泛函理论（DFT）计算得到的结果并不完全一致。在这里，我们基于g-CN和MoS的孔径排列模式构建了四种g-CN/MoS异质结。通过第一性原理和激发态动力学模拟研究了它们的形貌和光催化活性。通过系统比较g-CN/MoS异质结的界面结合能和电子结构（如能带结构、静电势和能带边缘位置），我们发现可以得到I型和II型能带排列结构。此外，计算得到的层间光生电子和空穴的寿命表明，II型g-CN/MoS倾向于一般的II型途径而不是Z型途径。这项研究可以深入理解g-CN/MoS范德华异质结构的光催化机制，这将对光催化应用有很大帮助。
