Two-Dimensional Type-II BP/MoSi2P4 vdW Heterostructures for High-Performance Solar Cells

Designing van der Waals (vdW) heterostructures has been considered to be a promising strategy for fabricating high-performance nanosized optoelectronic devices. Based on the first-principles calculations within density functional theory (DFT), we have demonstrated that a BP/MoSi2P4 vdW heterostructure possesses a direct band gap with a typical type-II band alignment, which can facilitate the effective separation of photogenerated electron–hole pairs. Compared with a MoSi2P4 monolayer, not only the hole carrier mobility but also the optical absorption intensity of the BP/MoSi2P4 heterostructure can be enhanced significantly. The predicted photoelectric conversion efficiency (PCE) for the BP/MoSi2P4 heterostructure can reach up to 22.2%, which is competitive with other existing two-dimensional (2D) heterostructures studied previously. Our findings indicate that the 2D BP/MoSi2P4 heterostructure can be a good candidate for new optoelectronic nanodevices.