Intermediate Bands in Zero-Dimensional Antimony Halide Perovskites

TL;DR

This study uses density functional theory to analyze a zero-dimensional antimony halide perovskite, revealing intermediate bands that enhance electronic properties and suggest potential for lead-free optoelectronic applications.

Contribution

It demonstrates the formation of intermediate bands in zero-dimensional perovskites and explores their impact on electronic structure and optoelectronic potential.

Findings

Direct band gap near the solar spectrum peak

Efficient electron carrier transport due to effective masses

Formation of intermediate bands from orbital hybridization

Abstract

Using density functional theory, the structural and electronic-structure properties of a recently discovered, zero-dimensional antimony halide perovskite are studied. It is found that the herein considered material EtPySbBr$_\mathrm{6}$ exhibits very promising electronic-structure properties: a direct band gap close to the peak of the solar spectrum and effective masses allowing for efficient carrier transport of electrons in particular. These results are rationalized by analysis of the electronic structure, which reveals the formation of intermediate bands due to orbital-hybridization effects of the Sb s-states. This study shows that the formation of intermediate bands can lead to highly favorable electronic-structure properties of zero-dimensional perovskites and discusses the possibility of fabricating lead-free HaPs with promising optoelectronic properties by targeted substitution of ions and emergence of intermediate bands. These insights are important when understanding and further enhancing the capabilities of antimony and other promising lead-free compounds.