Exploring the application of Janus MoSi2N2P2 monolayers in nanodevices and phototransistors

The MA2Z4 family of materials exhibits excellent thermal and mechanical stability, unique electronic properties, and ultrahigh carrier mobility, rendering them highly promising for low-dimensional nanodevice applications. Using atomic substitution modeling, we computationally investigate the structural configurations of α1- and α2-phase in three monolayers: MoSi2N2P2, Mo(SiNP)2-A, and Mo(SiNP)2-B. Our first-principles analysis reveals that these monolayers possess robust structural and mechanical stability alongside high carrier mobility, making them ideal candidates for next-generation nanoelectronics. Specifically, the simulations of pn-junction diodes based on Janus MoSi2N2P2 monolayers demonstrate excellent rectification effects, while α1-phase MoSi2N2P2 pn-junction diodes exhibit negative differential resistance at finite bias. Furthermore, the pin-junction field-effect transistors show distinct behavior under positive and negative gate voltages, and the associated phototransistors display robust photovoltaic responses in the violet and ultraviolet regions, underscoring their significant optoelectronic potential. These results demonstrate the potential of Janus MA2Z4-based monolayers for future high-performance electronic and optoelectronic applications.