Gas Sensing with h-BN Capped MoS2 Heterostructure Thin Film Transistors

TL;DR

This paper demonstrates that h-BN capping on MoS2 thin film transistors enables selective gas sensing with improved stability, allowing detection of various chemical vapors without hindering sensor performance.

Contribution

The study introduces a novel h-BN capping technique for MoS2 sensors that enhances stability and maintains gas detection capabilities, advancing 2D material-based chemical sensing.

Findings

h-BN capping does not prevent gas detection in MoS2 sensors

h-BN layer improves device stability and prevents degradation

MoS2/h-BN sensors detect multiple chemical vapors effectively

Abstract

We have demonstrated selective gas sensing with molybdenum disulfide (MoS2) thin films transistors capped with a thin layer of hexagonal boron nitride (h-BN). The resistance change was used as a sensing parameter to detect chemical vapors such as ethanol, acetonitrile, toluene, chloroform and methanol. It was found that h-BN dielectric passivation layer does not prevent gas detection via changes in the source-drain current in the active MoS2 thin film channel. The use of h-BN cap layers (thickness H=10 nm) in the design of MoS2 thin film gas sensors improves device stability and prevents device degradation due to environmental and chemical exposure. The obtained results are important for applications of van der Waals materials in chemical and biological sensing.