Detail:
Abstract: Understanding the cation incorporation into copper sulfide nanocrystals (NCs) process has become a major emphasis in our research group. In one recent study, we prepared unique biconcave djurleite Cu1.94S nanoplatelets (NPls) from template CuInS2 (CIS) NPls via a cation exchange (CE) reaction. We also prepared different heterostructures by incorporating different amounts of Ag+ into covellite CuS NPls. When a relatively small amount of Ag+ was provided, CuS-Ag2S plate-satellite heterostructures were produced by CE reactions occurring at the corners of the template hexagonal NPls. In contrast, biconcave-particle Ag2S-Ag heterostructures were obtained via the nanoscale Kirkendall effect when starting with 0.5 mmol of Ag+. In yet another related project, we incorporated indium and tin into Cu1.81S-ZnS sandwich-like nanoheterostructures (NHs). The selectivity of cation incorporation depended upon both the cation itself and the hetero-domains in which CE reactions take place. These studies not only provide a better understanding of the relationships among composition, morphology and crystal structure for copper sulfide-based NCs, but also provide new pathways to previously inaccessible morphologies, compositions, and heterostructures. Biosketch: Yang Liu was born in Shanxi, China in May 1991. He earned his BS degree in Material Physics from Taiyuan University of Technology in 2013. He then joined the Department of Chemical and Biological Engineering at the University at Buffalo (SUNY), where he is a Ph.D. candidate under the guidance of Prof. Mark T. Swihart.. His present research interests focus on the solution-phase synthesis, interconversion, cation incorporation, and application of copper chalcogenide-based nanomaterials. As a Ph.D. candidate, Yang has contributed 12 papers in journals including Journal of the American Chemistry Society, ACS Nano, and Chemistry of Materials.
