Mo_1-xW_xSe₂-Based Schottky Junction Photovoltaic Cells

We developed Schottky junction photovoltaic cells based on multilayer Mo_1-xW_xSe₂ with x = 0, 0.5, and 1. To generate built-in potentials, Pd and Al were used as the source and drain electrodes in a lateral structure, and Pd and graphene were used as the bottom and top electrodes in a vertical structure. These devices exhibited gate-tunable diode-like current rectification and photovoltaic responses. Mo_0.5W_0.5Se₂ Schottky diodes with Pd and Al electrodes exhibited higher photovoltaic efficiency than MoSe₂ and WSe₂ devices with Pd and Al electrodes, likely because of the greater adjusted band alignment in Mo_0.5W_0.5Se₂ devices. Furthermore, we showed that Mo_0.5W_0.5Se₂-based vertical Schottky diodes yield a power conversion efficiency of ∼16% under 532 nm light and ∼13% under a standard air mass 1.5 spectrum, demonstrating their remarkable potential for photovoltaic applications.