Bismuth and Antimony Based Oxyhalides and Chalcohalides as Potential Optoelectronic Materials

TL;DR

This paper evaluates bismuth and antimony oxyhalides and chalcohalides using first principles calculations, identifying promising compounds for optoelectronic applications like solar cells and detectors.

Contribution

It provides a systematic assessment of these materials' properties and trends, highlighting potential candidates for optoelectronic devices.

Findings

Identified three promising compound types for solar absorption, transparency, and radiation detection.

Analyzed electronic structure and crystal geometry relationships.

Provided insights into band-edge dispersion and carrier effective mass.

Abstract

In the last decade the ns$^2$ cations (e.g., Pb$^{2+}$ and Sn$^{2+}$) based halides have emerged as one of the most exciting new classes of optoelectronic materials, as exemplified by for instance hybrid perovskite solar absorbers. These materials not only exhibit unprecedented performance in some cases, but they also appear to break new ground with their unexpected properties, such as extreme tolerance to defects. However, because of the relatively recent emergence of this class of materials, there remain many yet to be fully explored compounds. Here we assess a series of bismuth/antimony oxyhalides and chalcohalides using consistent first principles methods to ascertain their properties and obtain trends. Based on these calculations, we identify a subset consisting of three types of compounds that may be promising as solar absorbers, transparent conductors, and radiation detectors. Their electronic structure, connection to the crystal geometry, and impact on band-edge dispersion and carrier effective mass are discussed.