First principles calculations of electrical and optical properties of Cu_3N/MoS_2 heterostructure with tunable bandgaps

摘要

In this work, based on the first principle calculation of density-functional theory (DFT), the surface energy of the low index surfaces of Cu_3N and MoS_2 is calculated, and the binding energy, interlayer distance, band structure, density of state, electron density difference and optical properties of the Cu_3N/MoS_2 heterostructure are systematically studied. The results show that different stacking and interlayer distance will affect the stability of the heterostructure. In addition, the change of the interlayer distance will also lead to the change of bandgap. It shows that the Cu_3N/MoS_2 heterostructure has the property of tunable bandgaps. Through the analysis of the imaginary part of dielectric function and optical absorption coefficient, Cu_3N/MoS_2 heterostructure has good optical properties in ultraviolet, visible and infrared regions, and has strong absorption ability for visible light. In a word, Cu_3N/MoS_2 heterostructure has stable structure and excellent photoelectric performance, which has a good potential and broad application prospect in photoelectric devices, visible light absorption and infrared light conversion.