Abstract

Graphene oxide (GO) membranes made of 2D GO nanosheets have attracted increasing attention for gas separation. However, the gas transport mechanism for these membranes is unclear due to inconsistent permeation and separation results reported in the literature. It appears that synthesis method and characteristics of GO sheets (size or defects) affect the permeability and separation characteristics of these membranes. This talk will give an overview of our recent research efforts on GO membranes for gas separation with a focus on clarifying the transport mechanism of these membranes. We proposed an inter-sheet and intra-sheet two-pathway model to explain the permeation and separation results of GO membranes obtained in our study.  We found that gas permeation and separation through GO membranes are controlled by transport through the highly tortuous inter-sheet space and intra-sheet defects of extremely low porosity.   It is difficult to control the GO membrane structure that defines both transport pathways, leading to variation of permeation and separation properties reported in the literature.  We also investigated structure changes and gas permeation properties of GO membranes made by different preparation methods, and from GO sheets of different sizes synthesized by different oxidation methods (Hummers vs. Brodie). Our recent efforts on membrane fabrication with narrow inter-sheet spacing height resulted in GO membranes with improved (H2/CO2) separation performance.  However, the results suggest that it is more desirable to pursue membranes using 2D nanosheets containing crystalline micropores such as zeolites, metal-organic-frameworks (MOF) or coordination-polymer-frameworks (COF), rather than the 2D graphite or GO nanosheets.

Biography

Jerry Y.S. Lin is a Regents’ Professor at Arizona State University.  He was department chair of chemical engineering at ASU from 2006-2009 after his 13 year appointment as a faculty member at University of Cincinnati.  Dr. Lin’s main research areas are membrane science, adsorption/catalysis, and energy storage.  He has published about 400 papers in these areas and is an inventor of 9 US and European patents.  As one of the most cited authors in the field of chemical engineering (per Elsevier-Scopus/Shanghai Ranking), Dr. Lin’s papers have been cited over 28,000 per google/scholar.  Dr. Lin received several awards including AIChE Institute Award for Excellence in Industrial Gas Technologies (2009) and AIChE Gerhold Award (2021), and is an elected fellow of American  Society for the Advancement of Science (AAAS), American Institute of Chemical Engineers (AIChE), and North American Membrane Society (NAMS).  He currently serves as co-Editor-in-Chief of Journal of Membrane Science and Journal of Membrane Science Letters.

Seminar sponsored by the Department of Chemical and Biomolecular Engineering.