Interfacial Charge Transfer and Photovoltaic Properties in C-60/MoS2 0D-2D van der Waals Heterostructures

Constructing 0D-2D mixed-dimensional van der Waals (MvdW) heterostructures is an effective strategy to improve photovoltaic properties of photovoltaic devices. However, addressing the underlying mechanism on the role of array periodicity of 0D and thickness of 2D components on the photovoltaic properties at the atomic-level still remains challenging. Herein, the interfacial charge transfer and photovoltaic conversion mechanism in C-60/MoS2 0D-2D MvdWs based on the atomic-bond-relaxation consideration, Marcus theory, modified-detailed balance principle, and first-principles calculations are investigated. Compared with the case of monolayer MoS2, it is found that C-60/MoS2 MvdW heterostructures have lower interface reflectivity and type II band alignment, leading to obvious improvement of power conversion efficiency (PCE) from 0.27% to 1.40%. Moreover, the photovoltaic properties can be tuned by changing the array periodicity of the C-60 and the thickness of the MoS2, and the optimized PCE can be up to 5.35%. The results reveal that the modification of 0D C-60 is an effective strategy to enhance the photovoltaic properties of MoS2-based solar cells.