Comparative Analysis of the Interfacial Structure and Properties of BiOX/BiOY (X, Y = F, Cl, Br, and I) Heterostructures through DFT Calculations

This study focuses on the systematic investigation ofthe microstructure,interfacial energy, and electronic structure of six BiOX/BiOY heterostructuresconstructed using four bismuth oxyhalide materials. Utilizing densityfunctional theory (DFT) calculations, the study provides fundamentalinsights into the interfacial structure and properties of these heterostructures.The results indicate that the formation energies of BiOX/BiOY heterostructuresdecrease in the order of BiOF/BiOI, BiOF/BiOBr, BiOF/BiOCl, BiOCl/BiOBr,BiOBr/BiOI, and BiOCl/BiOI. BiOCl/BiBr heterostructures were foundto have the lowest formation energy and were the most easily formed.Conversely, the formation of BiOF/BiOY heterostructures was observedto be unstable and difficult to achieve. Furthermore, the interfacialelectronic structure analysis revealed that BiOCl/BiOBr, BiOCl/BiOI,and BiOBr/BiOI displayed opposite electric fields that facilitatedelectron-hole pair separation. Therefore, these research findingsprovide a comprehensive understanding of the mechanisms underlyingthe formation of BiOX/BiOY heterostructures and present theoreticalguidance for the design of innovative and efficient photocatalyticheterostructures, with an emphasis on BiOCl/BiOBr heterostructures.This study highlights the advantages of distinctively layered BiOXmaterials and their heterostructures, which offer a wide range ofband gap values, and demonstrates their potential for various researchand practical applications. Themicrostructure and properties of BiOX/BiOY (X, Y = F,Cl, Br, I) heterostructures are systematically compared by DFT. Meanwhile,the results clarify the excellent photocatalytic activity for sixBiOX/BiOY heterostructures. Based on the comprehensive understandingof the mechanism of BiOX/BiOY heterojunction formation, the more prominentpotential of BiOCl/BiOBr heterostructures is reliably predicted.

Automated summary

This study investigates the microstructure, interfacial energy, and electronic structure of six BiOX/BiOY heterostructures constructed using four bismuth oxyhalide materials. The formation energies of the heterostructures decrease in a specific order, with BiOCl/BiBr having the lowest formation energy. The study also reveals the potential of BiOCl/BiOBr heterostructures for efficient photocatalytic applications based on their excellent interfacial properties.