Magnon sensing of NO, NO$_2$ and NH$_3$ gas capture on CrSBr monolayer

TL;DR

This study uses first-principles calculations to explore how monolayer CrSBr can detect and capture harmful gases like NO, NO2, and NH3, highlighting defect engineering to improve sensitivity and magnetic response.

Contribution

It demonstrates the potential of CrSBr monolayer for gas sensing and capture, emphasizing the role of Br vacancies in enhancing adsorption and magnonic properties.

Findings

Br vacancies increase adsorption of NH3, NO, NO2

Vacancies induce a selective shift in magnon dispersion

CrSBr shows promise for magnonic gas sensing devices

Abstract

Air pollution and greenhouse emissions are a significant problem across various sectors, urging the need for advanced technologies to detect and capture harmful gases. In recent years, two-dimensional (2D) materials have attracted an increasing attention due to their large surface-to-volume ratio and reactivity. Herein, we investigate the potential of single-layer CrSBr for gas sensing and capturing by means of first-principles calculations. We explore the adsorption behaviour of different pollutant gases (H$_2$S, NH$_3$, NO, NO$_2$, CO and CO$_2$) on this 2D ferromagnet and the impact of intrinsic defects on its magnetic properties. Interestingly, we find that Br vacancies enhance the adsorption of NH$_3$, NO and NO$_2$ and induces a selective frequency shift on the magnon dispersion. This work motivates the creation of novel magnonic gas sensing devices based on 2D van der Waals magnetic materials.