Two-Dimensional Transition Metal Dichalcogenides: A New Platform for High-Efficiency Photovoltaic Devices

Abstract

This work presents a comprehensive analysis of two-dimensional transition metal dichalcogenides (TMDCs), including MoS₂, WS₂, MoSe₂, and WSe₂, as promising materials for photovoltaic applications. Using a combination of experimental methods, including Raman spectroscopy, atomic force microscopy, and transmission electron microscopy, as well as numerical modeling, key relationships between structural features, electronic properties, and photovoltaic efficiency were established.
It is shown that monolayer TMDCs possess a direct band gap and pronounced excitonic effects, which ensure efficient absorption in the 600–700 nm range, corresponding to the maximum of the solar spectrum. The results of the study indicate that MoS₂ demonstrates the highest efficiency, approximately 7.2%, while WSe₂ combines good optical and electrical properties with enhanced stability. At the same time, WS₂ and MoSe₂ require further optimization of technological parameters.
The energy band alignment in MoS₂/WS₂-type heterostructures confirms the potential of interlayer carrier separation for reducing recombination losses and improving device efficiency. Key scientific challenges are discussed, including the scalability of synthesis, control of layer thickness, and material stability under environmental conditions.
Thus, TMDCs represent a new platform for the development of thin-film, flexible, and transparent solar cells, opening the way toward next-generation high-efficiency photovoltaic technologies.