Tuesday, 3 October 2017: 15:30
Chesapeake E (Gaylord National Resort and Convention Center)
Novel condensed matter systems can be understood as new compositions of elements or old materials in new forms. According to the definition, various new condensed matter systems have been developed or are under development in the recent years. 2D layered materials, including graphene, transition metal dichalcogenides (TMDs) allow the scaling down to atomically thin thicknesses and possess unique physical properties under dimensionality confinement. Chemical vapor deposition (CVD) process is the most popular approach for all kind of 2D materials due to its high yield and quality. Nevertheless, the need for high temperature and the relatively long process time within each cycle hinders for commercial development in terms of production cost. However, the transfer procedure has become one of the major limitations of the overall performance. In the first part of my talk, I will present several approaches, including ultra-fast microwave heating, plasma selective reaction, controlled segregation process by laser irradiation and metal vapers-assisted growth processes developed in my lab these years to directly grow graphene with controllable thicknesses on arbitrary substrates without any extra transfer process. In the 2nd part of my talk, I will also introduce the development of various methods, including laser irradiation assisted-selenization (LIAS) process, fast microwave annealing and plasms enhance selenization processes on different two-dimensional transition metal dichalcogenides materials in my lab. The detailed formation mechanisms, microstructures and physical performances as well as its applications in gas sensors, photodetector and water splitting behaviors based on these two 2D materials were reported and investigated.