The Center for Computational and Integrative Biology will be hosting Dr. Yugang Sun, Professor of the Department of Chemistry at Temple University.
Dr. Sun will be speaking on the following topic:
Title: Multifunction of Pt Nanocrystals in Photocatalytic HER
Abstract: Platinum (Pt) nanocrystals are usually used in chemical reactions because of their excellent catalytic performance, for example, photocatalytic water splitting of water. In a typical design, Pt nanocrystals can accept photo-excited electrons from light absorbers such as semiconductor quantum dots (QDs) to catalyze hydrogen evolution reaction (HER) . Charge transfer from QDs to Pt nanocrystals is very inefficient, and shuttle molecules (e.g., methylviologen) or other shuttle species are necessary to facilitate the charge transfer. In this presentation, a binary superparticles made of Pt nanocrystals and AgCl nanocrystals  will be discussed as a new class of Pt-based nanostructures that can directly accept photoexcited electrons from QDs without assistance of mediate molecules to efficiently catalyze HER with internal quantum yield of 8.6%. In addition to receiving electrons from semiconductor QDs, Pt nanocrystal can also absorb visible light to generate energetic electrons, which can inject to conduction band of a semiconductor to drive chemical reactions including HER. Depositing Pt nanocrystals on spherical SiO2 particles can significantly enhance visible absorption coefficient of the Pt nanocrystals due to the unique scattering modes near the SiO2 particles. In SiO2@Pt nanocrystals@TiO2 core-shell nanostructures, the enhancement in visible absorption enables the efficient generation of energetic electrons in photoexcited Pt nanocrystals, which can easily transfer to the TiO2 surface layer to drive HER and many other chemical reactions .
The seminar will take place, November 1, 2016 at 12:30pm in the Science Lecture Hall.