First-principles study on the strain-mediated g-C3N4/blue phosphorene heterostructures for promising photocatalytic performance

A Review of Bandgap Engineering and Prediction in 2D Material Heterostructures: A DFT Perspective

The advent of two-dimensional (2D) materials and their capacity to form van der Waals (vdW) heterostructures has revolutionized numerous scientific fields, including electronics, optoelectronics, and energy storage. This paper presents a comprehensive investigation of bandgap engineering and band structure prediction in 2D vdW heterostructures utilizing density functional theory (DFT). By combining various 2D materials, such as graphene, hexagonal boron nitride (h-BN), transition metal dichalcogenides, and blue phosphorus, these heterostructures exhibit tailored properties that surpass those of individual components. Bandgap engineering represents an effective approach to addressing the limitations inherent in material properties, thereby providing enhanced functionalities for a range of applications, including transistors, photodetectors, and solar cells. Furthermore, this study discusses the current limitations and challenges associated with bandgap engineering in 2D heterostructures and highlights future prospects aimed at unlocking their full potential for advanced technological applications.

The strain regulated physical properties of PbI2/g-C3N4for potential optoelectronic device

The van der Waals (vdW) heterostructures of Z-scheme PbI2/g-C3N4with an indirect bandgap have gained much attention in recent years due to their unique properties and potential applications in various fields. However, the optoelectronic characteristics and strain-modulated effects are not yet fully understood. By considering this, six stacking models of PbI2/g-C3N4are proposed and the stablest structure is selected for further investigation. The uniaxial and biaxial strains (-10%-10%) regulated band arrangement, charge distribution, optical absorption in the framework of density functional theory are systematically explored. The compressive uniaxial strain of -8.55% changes the band type from II→I, and the biaxial strains of -7.12%, -5.25%, 8.91% change the band type in a way of II→I→II→I, acting like the 'band-pass filter'. The uniaxial strains except -10% compressive strain, and the -6%, -4%, 2%, 4%, 10% biaxial strains will enhance the light absorption of PbI2/g-C3N4. The exerted strains on PbI2/g-C3N4generate different power conversion efficiency (ηPCE) values ranging from 3.64% to 25.61%, and the maximumηPCEis generated by -6% biaxial strain. The results of this study will pave the way for the development of new electronic and optoelectronic materials with customized properties in photocatalytic field and optoelectronic devices.