Superior gas sensing properties of [formula omitted]-In[formula omitted]Se[formula omitted]: A first-principles investigation

Sherifdeen O Bolarinwa,Shahid Sattar,Abdullah A Alshaikhi

doi:10.1016/j.commatsci.2021.110880

Sherifdeen O Bolarinwa, Shahid Sattar + Show 1 more

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https://doi.org/10.1016/j.commatsci.2021.110880

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Abstract

Using first-principles calculations, we report structural and electronic properties of CO, NO2 and NO molecular adsorption on β-In2Se3 in comparison to a previous study on α-phase. Analysis and comparison of adsorption energies and extent of charge transfer indicates β-In2Se3 to be selective in detecting gas molecules. We found NO molecules acting as charge donor whereas CO and NO2 molecules as charge acceptors, respectively, experiencing physisorption in all cases. Owing to enhanced adsorption, faster desorption and improved selectivity of the gas molecules discussed in detail, we conclude β-In2Se3 to be a superior gas sensing material ideal for chemoresistive-type gas sensing applications.

Highlights

The need to identify gas leakage, toxic gases, and organic vapours for human and environmental safety is fundamental to develop next-generation sensing technologies
The optimized lattice constant of β-In2Se3 turns out to be 4.03 ̊A which is in good agreement to the experimental value of 4.025.50 It consists of five covalently bonded atomic sheets known as quintuple layers (QL) that are vertically stacked in the sequence Se-In-Se-In-Se atoms
Four anchoring sites have been considered with the centre of mass of the gas molecule initially positioned on top of multiple sites

Summary

Introduction

The need to identify gas leakage, toxic gases, and organic vapours for human and environmental safety is fundamental to develop next-generation sensing technologies. Gases that are by-products of our day-to-day activities (e.g., CO, NO2, and NO etc.) and toxic even at lower concentrations demand great attention. Different materials are employed in a bid to identify toxic gases which includes conducting polymers,[1,2,3] carbon nanotubes (CNTs),[4,5] and semiconducting metal oxides[6,7] to list a few. Conducting polymers are processed, but effects of humidity and degradation hamper their applicability.[8,9,10] On the other hand, metal oxides show prospects in sensing molecules, high operating temperature, large power consumption, and low selectivity have been a major issue in their commercial usage.[11,12,13] Owing to these obvious drawbacks, researchers have intensified efforts in exploring potential new materials that can efficiently detect gases at room temperature and standard environmental conditions while retaining high selectivity and sensibilities

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