Gas-Sensing Mechanisms and Performances of MXenes and MXene-Based Heterostructures

Abstract

MXenes are a class of 2D transition-metal carbides, nitrides, and carbonitrides with exceptional properties, including substantial electrical and thermal conductivities, outstanding mechanical strength, and a considerable surface area, rendering them an appealing choice for gas sensors. This manuscript provides a comprehensive analysis of heterostructures based on MXenes employed in gas-sensing applications and focuses on addressing the limited understanding of the sensor mechanisms of MXene-based heterostructures while highlighting their potential to enhance gas-sensing performance. The manuscript begins with a broad overview of gas-sensing mechanisms in both pristine materials and MXene-based heterostructures. Subsequently, it explores various features of MXene-based heterostructures, including their composites with other materials and their prospects for gas-sensing applications. Additionally, the manuscript evaluates different engineering strategies for MXenes and compares their advantages to other materials while discussing the limitations of current state-of-the-art sensors. Ultimately, this review seeks to foster collaboration and knowledge exchange within the field, facilitating the development of high-performance gas sensors based on MXenes.

MXene-Based Chemo-Sensors and Other Sensing Devices

“… Gas sensing mechanism of the pristine 2D MXenes and the corresponding energy band diagram. Reprinted from [ 126 ]. …”

Effects of Visible Light on Gas Sensors: From Inorganic Resistors to Molecular Material-Based Heterojunctions

“…The ability to detect and quantify specific gases or volatile organic compounds is essential for ensuring safety, quality and compliance [ 1 , 2 ]. Traditionally, gas sensors have relied on well-established principles of chemical interactions, which are inherently affected by factors like temperature, humidity and the presence of interfering gases [ 3 , 4 ].…”