April 22 - 26, 2024
Seattle, Washington
May 7 - 9, 2024 (Virtual)
Symposium Supporters
2024 MRS Spring Meeting & Exhibit
EN11.04.02

Air-Stable Bismuth Sulfobromide (BiSBr) Visible-Light Absorbers: Optoelectronic Properties and Potential for Energy Harvesting

When and Where

Apr 25, 2024
8:45am - 9:00am
Room 335, Level 3, Summit

Presenter(s)

Co-Author(s)

Xiaoyu Guo1,Yi-Teng Huang1,Hugh Lohan1,2,Junzhi Ye1,Yuanbao Lin1,Juhwan Lim3,Nicolas Gauriot3,Szymon Zelewski3,Daniel Darvill2,Aron Walsh2,Huimin Zhu4,1,Akshay Rao3,Iain McCulloch1,Robert Hoye1

University of Oxford1,Imperial College London2,University of Cambridge3,University of Strathclyde4

Abstract

Xiaoyu Guo1,Yi-Teng Huang1,Hugh Lohan1,2,Junzhi Ye1,Yuanbao Lin1,Juhwan Lim3,Nicolas Gauriot3,Szymon Zelewski3,Daniel Darvill2,Aron Walsh2,Huimin Zhu4,1,Akshay Rao3,Iain McCulloch1,Robert Hoye1

University of Oxford1,Imperial College London2,University of Cambridge3,University of Strathclyde4
ns<sup>2</sup> compounds have recently attracted considerable interest due to their potential to replicate the defect tolerance of lead-halide perovskites and overcome their toxicity and stability limitations. However, only a handful of compounds beyond the perovskite family have been explored thus far. Herein, we investigate bismuth sulfobromide (BiSBr), which is a quasi-one-dimensional semiconductor, but very little is known about its optoelectronic properties or how it can be processed as thin films. We develop a solution processing route to achieve phase-pure, stoichiometric BiSBr films (<i>ca.</i> 240 nm thick), which we show to be stable in ambient air for over two weeks without encapsulation. The bandgap (1.91 ± 0.06 eV) is ideal for harvesting visible light from common indoor light sources, and we calculate the optical limit in efficiency (i.e., spectroscopic limited maximum efficiency, SLME) to be 43.6% under 1000 lux white light emitting diode illumination. The photoluminescence lifetime is also found to exceed the 1 ns threshold for photovoltaic absorber materials worth further development. Through X-ray photoemission spectroscopy and Kelvin probe measurements, we find the BiSBr films grown to be n-type, with an electron affinity of 4.1±0.1 eV and ionization potential of 6.0±0.1 eV, which are compatible with a wide range of established charge transport layer materials. This work shows BiSBr to hold promise for indoor photovoltaics, as well as other visible-light harvesting applications, such as photoelectrochemical cells, or top-cells for tandem photovoltaics.

Keywords

absorption | electronic structure | solution deposition

Symposium Organizers

Andrea Crovetto, Technical University of Denmark
Annie Greenaway, National Renewable Energy Laboratory
Xiaojing Hao, Univ of New South Wales
Vladan Stevanovic, Colorado School of Mines

Session Chairs

Galina Gurieva
Rasmus Nielsen

In this Session