报告题目：Analytical and Physical Chemistry Strategies for Light Emissions of Graphene Quantum Dots
报告人：Prof. Zhifeng Ding, Department of Chemistry, The University of Western Ontario, London, ON N6A 5B7, Canada
Our research lab at The University of Western Ontario focuses on 4 research themes: scanning electrochemical microscopy of live cells and corrosion processes, ionic liquids as novel electrolytes, electrochemiluminescence or electrogenerated chemiluminescence (ECL) and solar cells. Herein, we demonstrate our progresses on carbon nanomaterials for ECL and white light-emitting electrochemical cells.
ECL is the process in which electrogenerated radicals form excited species that emit light without the need for an external light source (Struct. Bonding 2005, 118, 1; J. Electrochem. Soc. 2016, 163, H3116). ECL is a powerful analytical technique that is fast, highly sensitive and selective, requires low quantity.
Ding et al. demonstrated ECL of silicon QDs a decade ago (Science 2002, 296, 1293). Since then, a wide range of semiconductor QDs such as Ge, CdTe, CdSe, CdSe/ZnSe, and PbS, as well as graphene/carbon QDs (J. Am. Chem. Soc. 2007, 129, 744) have been investigated for the ECL in visible or near-infrared (NIR) region. Gold clusters and PbS QDs have been discovered to be efficient ECL emitters by the Ding group at Western (Acc. Chem. Res. 2017, 50, 218). However, in most cases, the inherent optical and electrochemical properties of other interesting materials do not translate into efficient ECL, due to the surface state induction effect and inefficient electron transfer rate. We report highly efficient photoluminescence and ECL of carbon nanomaterials in the presence of sulfate radical anion as an oxidative coreactant or others. The ECL mechanisms were elucidated by various electroanalytical methods (for instance, Carbon 2018, 129, 45). Light-emitting electrochemical cells of the graphene quantum dots are anticipated for efficient and low cost white light emitting diodes.
Dr. Zhifeng Ding is a full professor of chemistry at The University of Western Ontario, London, Ontario Province, Canada. He received his B.Sc. degree in chemistry with the highest honor at Southeast University, M.Sc. in coordination chemistry under the supervision of Prof. Xiaozeng You at Nanjing University and earned his Ph.D. in physical and analytical electrochemistry in the Girault group at Swiss Federal Institute of Technology in Lausanne (EPFL). After 3 years postdoctoral research in Allen J. Bard’s Lab at The University of Texas at Austin, he moved to his present Canadian university as faculty member. His research focuses on scanning electrochemical microscopy, ionic liquids as novel electrolytes, electrochemiluminescence and solar cells. Recently, his group has utilized He has published more than 150 papers, filed more than 4 US and Chinese patents and received several awards including most recently: Premier’s Research Excellence Award 2003; Western Science Distinguished Research Professor 2014-2015; Western University Faculty Scholar 2015-2016; 2017 Canadian Society for Chemistry W.A.E. McBryde Medal for his significant achievement in analytical chemistry; 2017 and 2018 Western Vanguard Awards for filing and licensing patents in solar energy. 2018 Ertl (2007 Nobel Laureate) award for electrochemistry and electrocatalysis for his contributions to solar cell research.