Design of a New Photo-Diode Based on (α-PbO)/(α-SnO) Lateral Heterostructure

α-SnO and α-PbO monolayers are two stable nanostructures that are separately synthesized by epitaxial growth on the same substrate (SiO2/Si) with superior functionalities, making them industrially important material for many applications. We have theoretically predicted a new lateral heterostructures (α-PbO)n/(α-SnO)n formed by periodically repeating narrow SnO and PbO strips joined along their adjacent interface and investigated the structural, mechanical and electronic properties by using first-principles calculations. We demonstrate that creating these lateral heterostructures by α-PbO and by α-SnO monolayer materials will allow for adjusting various physical and chemical parameters such as tunable band gap, which are required to fit wide spectral range in optoelectronics applications. We obtained that the (α-PbO)7/(α-SnO)7 heterostructure shows an Anderson type-II band alignment where CBM is located at α-PbO domain while VBM is located at α-SnO domain. Consequently, the photon-generated electron-hole pairs are spatially separated, resulting in much longer exciton lifetime compared to that of the two monolayers separately which needs to be confirmed by further experimental measurements. This new structure can be used as a forward p-n diode and offer an interesting optoelectronic properties.