Abstract: Modern electronics and optoelectronics require large-scale growth of semiconducting thin films, which would benefit the development of high-performance ultrathin and flexible devices. Two-dimensional (2D) transition metal dichalcogenides (TMDs) provide ideal semiconducting materials with attractive electronic and photonic properties. Towards to route to their practical applications, the controlled growth of 2D TMDs with well-designed composition, layer number, size, and structure is prerequisite. In this talk, I will present our recent progress on the controlled growth of 2D TMDs by chemical vapor deposition (CVD). Bilayer TMDs with a 100% selectivity, a variety of TMD-based heterostructures, and large-area continuous monolayer TMD films are all successfully obtained. Beyond TMDs, ongoing research activities also focus on the controlled synthesis of 2D transition metal carbides, known as MXenes. An universal functionalization method based on hexagonal boron nitride (hBN) interlayers has been developed to promote the application of 2D semiconductors in electronic biosensors.
Mengqiang (Mark) Zhao is currently an Assistant Professor in the Department of Chemical and Materials Engineering at NJIT. Before joining NJIT, he was a postdoctoral researcher in the Department of Physics and Astronomy at the University of Pennsylvania, followed by another postdoc training in the Department of Materials Science and Engineering at Drexel University. His research focuses on synthesis, characterization, and processing of nanoscale materials for energy, electronic, and sensing applications, such as next-generation energy storage devices and portable diagnostic devices to detect diseases and toxic chemicals in the environment. While a Ph.D. candidate at Tsinghua University in Beijing, Zhao developed an advanced catalyst composed of metal nanoparticles and metal oxides that significantly improves the manufacturing production yield of carbon nanotubes. That technology has been licensed by a nanomanufacturing company and the carbon nanotubes it produces are used widely in the lithium-ion battery industry. Among other projects, he developed efficient methods for the large-scale synthesis and processing of two-dimensional transition metal dichalcogenides and carbides for use in energy storage and electronic biosensing. He has obtained nine patents and published more than 100 articles in peer-reviewed journals including Nature, Nature Energy, Advanced Materials, Angewandte Chemie, and ACS Nano, etc.