报告主题: ZnO@C (core@shell) microspheres derived from spent coffee grounds as applicable non-precious electrode material for DMFCs
报告时间: 2018.5.20 13:00-13:45
报告人及简介: Hak Yong Kim, a professor of BIN Convergence Technology Department in Chonbuk National University, South Korea. He received a B.S. degree from the Department of Textile Engineering of Chonbuk National University (South Korea) in 1981. He received his M.S. degree in Textile Engineering from Seoul National University in 1983. Then he received his Ph.D. degree from same University in 1993. From 1993 to 1998, he worked at Fiber Research Division in Samyang Group R&D Center. He became a professor at Chonbuk National University in 1998. He was made Director of Center for Healthcare Technology &Development of Chonbuk National University in 2004. Meanwhile, he was a visiting Professor at University of Massachusetts (USA) in 2004 and King Saud University (Saudi Arabia) in 2010, respectively. His research interests center on biomaterials, polymer composites, inorganic materials, and carbon nanofibers. His main achievements include 338 published SCI journal papers with more than 9026 citations, H-index is 48 and 102 patents.
报告大纲: Although numerous reports have introduced non precious electrocatalysts for methanol oxidation,most of those studies did not consider the corresponding high onset potential which restricts utilizationin real fuel cells. In this study, a −90 mV [vs. Ag/AgCl] onset potential non-precious electrocatalyst isintroduced as an applicable anode material for the direct methanol fuel cells. Moreover, the proposedmaterial was prepared from a cheap and abundantly existing resource; the spent coffee grounds. Typically, the spent coffee grounds were facilely converted to core@shell (ZnO@C) microspheres through a two-step approach, involving chemical activation and a subsequent calcination attemperature of 700°C. Activation of the carbon derived from the spent coffee grounds was performedwith ZnCl2 which acts as pore-forming agent as well as a precursor for the ZnO. The structure andmorphology were characterized by XRD, SEM, and TEM analyses while the electrochemicalcharacterizations was evaluated by cyclic voltammetry (CV) technique. Besides the comparatively verylow onset potential, the introduced microspheres exhibited relatively high current density; 17 mA/cm2.Overall, based on the advantages of the green source of carbon and the good electrocatalytic activity, the spent coffee grounds-derived carbon can be considered a promise anode material for the DMFCs.