Professor Peng Wang
Reduced graphene oxide membranes: fabrication and applicationsDATE:
Thursday, April 27, 2017TIME:
2:00 - 4:00 p.m.LOCATION:
Building 5 · Level 5 · Room 5209
Reduced graphene oxide (rGO) has attracted considerable interest recently as the low cost and chemical stable derivative of pristine graphene with application in many applications such as energy storage, water purification, and electronic devices. This dissertation thoroughly investigated stacked rGO membrane fabrication process by vacuum-driven filtration, discovered asymmetry of the two surfaces of the rGO membrane, explored application perspectives of the asymmetric rGO membrane in fog collection and microstructure patterning, and disclosed membrane compaction issue during water filtration and species rejection. In more details, this dissertation revealed that, with suitable pore size, the filtration membrane substrate would leave its physical imprint on the bottom surface of the rGO membrane in the form of surface microstructures, which result in asymmetric dynamic water wettability properties of the two surfaces of the rGO membrane. The asymmetric wettability of the rGO membrane would lead to contrasting fog harvesting behavior of its two surfaces. The physical imprint mechanism was further extended to engineering pre-designed patterns selectively on the bottom surface of the rGO membrane. This dissertation, for the first time, reported the water flux and rejection kinetics, which was related to the compaction of the rGO membrane under pressure in the process of water filtration.
Bo Tang was born in Sichuan, China. He joined Professor Peng Wang's lab at the King Abdullah University of Science & Technology in 2014 for his PhD study in Environmental Science and Engineering. His research interest is to fabricate and synthesize graphene and other 2D based materials for water related application.