Nanodevice simulations and electronic transport properties of a two-dimensional PbBr2 monolayer

Two-dimensional (2D) wide bandgap semiconductors are promising blocks for applications in photodetections, spintronics and high energy radiation detection. Here, we probe the mechanical, biaxial strain-relate, electronic transport, and optoelectronic properties of PbBr2 monolayer with wide bandgaps using first-principles calculations. The 2D Young's modulus of PbBr2 monolayer is determined to be 14.68 N m � 1 and the shear modulus is calculated to be 5.83 N m � 1 at 300 K, revealing that PbBr2 monolayer is mechanically more flexible than other 2D materials, such as hexagonal-BN and MoB2. Interestingly, a specific forbidden bandwidth can be obtained by implementing a suitable strain on PbBr2 monolayer, and such effect leads to indirect bandgap semiconductor properties. Furthermore, various PbBr2 monolayer nanodevices, including p-n junction diodes, p-i-n junction field-effect transistors (FETs), and phototransistors, are designed and explored to investigate their transport properties. A variety of excellent transport properties, including prominent unidirectional transport, remarkable electrical anisotropy, obvious field-effect property, strong photoelectric response, and prominent absorption characteristics in the ultraviolet region, have been observed in these nanodevices. Our results unveil the multifunctional nature and superior performance of PbBr2 monolayer and suggest a practical configuration for the experimental realization in next-generation semiconductor nanodevices.