Strategic review on chemical vapor deposition technology-derived 2D material nanostructures for room-temperature gas sensors

Abstract

The significance of two-dimensional (2D) materials including graphene and transition metal dichalcogenides has been escalating in gas sensor technology owing to detection of gases at room temperature (RT) and good mechanical flexibility. The operation of gas sensors at RT removes the need for micro-heaters from traditional gas sensors and also ensures miniaturization with extremely low power consumption to meet the requirements of advanced applications. Recent significant progress in the growth of 2D materials via chemical vapor deposition (CVD) technology allows industrial production of 2D materials-based gas sensor devices. In this review, we focus on the recent progress in RT gas sensors employing CVD-grown 2D material nanostructures. First, fundamentals and growth mechanisms of the different CVD-grown nanostructures (0D, 1D, 2D, and 3D) are elaborated to get a profound understanding of growth on rigid and flexible substrates. Second, we thoroughly discuss strategies toward novel RT gas sensing properties of CVD-grown 2D materials. The newly introduced specific sensing properties by the different nanostructures are extensively elucidated, addressing structure–property correlations. Third, state-of-the-art research endeavors to directly build gas sensors on emerging flexible and wearable sensing platforms are discussed. Finally, we highlight current challenges and future outlook of 2D materials-based gas sensors by employing a mature CVD technology of the electronics industry for practical sensing applications.