报告题目: How hydrophilic can a hydrophilic surface be?
报 告 人： 汪大洋 （教授，澳大利亚皇家墨尔本理工大学）
This presentation will focus mainly on our recent study of how the macroscopic wetting behaviour of charged surfaces is correlated with their microscopic chemical nature of the surface ionic groups. In this work polyelectrolyte multilayers (PEMs) were used as model charged surfaces.1 With the aid of sum frequency generation and X-ray photoelectron spectroscopy, we demonstrate the surface wetting behaviour of the PEMs is more closely correlated with the configurational geometry rather than hydrate strength of the uncompensated ionic groups on the surface capping layers. The lessons learnt from the surface wetting and the internal structures of as-prepared PEMs have successfully been translated to an innovative superoleophobic coating strategy, which is simple, versatile, cost-effective, and nanostructure-independent comparing to currently available ones. This has enabled us to easily transform conventional stainless steel meshes to highly effective filters for oil-water separation in high separation efficiency and high water flux, which can be easily scaled up for industrial oil/water separations such as oil spill cleanup in seawater.
Liu, X.; Leng, C.; Yu, L.; He, K.: Brown, L. J.; Chen, Z.; Cho, J.; Wang, D. “Ion-Specific Oil Repellency of Polyelectrolyte Multilayers in Water: Molecular Insight into Charged Surface Hydrophilicity” Angew. Chem. Int. Ed. 2015, 54, 4851 –4856.
He, K.; Duan, H.; Chen, G. Y.: Liu, X.; Yang, W.; Wang, D.; “Cleaning of Oil Fouling with Water Enabled by Zwitterionic Polyelectrolyte Coatings: Overcoming the Imperative Challenge of Oil-Water Separation Membranes, ACS Nano 2015, 9 9188-9198
Dayang Wang is Professor of Chemical Engineering at the School of Civil, Environmental, and Chemical Engineering at the RMIT University, Melbourne, Australia, and Fellow of the Royal Society of Chemistry (FRSC). Prior to his current position, he was Research Professor of Physical Chemistry at the Ian Wark Research Institute, University of South Australia, in Adelaide, Australia. Before moving to Australia in 2010, he was group leader at the prestigious Max Planck Institute of Colloids and Interfaces (MPI-KG), in Potsdam, Germany, and held that role for seven years. As a post-doctoral fellow at the MPI-KG from 1999-2003, he received the highly esteemed Alexander von Humboldt Research Fellowship (2002). He completed his PhD at Jilin University, where he studied chemistry, in 1998. Till now, Dayang has published 4 book chapters and 120 articles in peer-reviewed leading journals in Chemistry and Materials Science. According to ISI Web of Science (Research ID: A-6676-2012), his index is 41 with total citations of 4900 over 120 publications. He is a co-inventor on 2 PCT patent applications on water treatment technology, one of which has already led to a manufacture license deal ($450K) with Hyflux, Singapore. His research interests include interface adsorption and transfer, crystallization, self-assembly, hydrogel, and encapsulation and delivery.