2D nanomaterials

2D materials, which are sub-nanometer-scale layered materials held together by van der Waals forces, are considered promising for various electrical and electronic applications. We are focusing on how to synthesize 2D materials efficiently using liquid exfoliation and chemical vapor deposition methods. In particular, the semiconducting 2D MX2 and M2X3 (M=metal, X=chalcogenide) materials could be utilized in various semiconductor devices. We further investigate the memory and logic devices.

Chemical Vapor Deposition (CVD) is one of the promising ways to synthesize large-area, high-quality 2D materials such as graphene, MoS2,  etc.  We investigate a facile route to obtain such 2D materials using gas-phase and solution-based precursors. Furthermore, we develop solution-based precursors to easily synthesize the wafer-scale and high-quality 2D materials using thermal reduction reaction with low temperature.

We develop RT gas sensing devies using various 2D materials and have introduced a strategy to imporve performance by integrating metal-oxide nanostructure heterostructure with 2D materials. We also design light-induced (UV to infrared) chemoresistive gas sensors, where visible-light illumination enables stable, highly responsive RT operation. These 2D material-based chemoresistive gas sensors are promising candidates for future electronic-nose applications.

We develop thermoelectric materials and devices for near-room-temperature energy harvesting and solid-state cooling. By employing low-dimensional and heterostructured material designs, we enhance thermoelectric performance through controlled charge and heat transport. These thermoelectric systems are promising candidates for self-powered sensors and next-generation thermal management applications.