Journal of Membrane Science & Technology

Nanostructured polymer-graphene hybrid coatings for membrane separations and energy applications

2^nd International Conference on Membrane Science and Technology

September 13-14, 2018 | London, UK

Michael Z Hu

Oak Ridge National Laboratory, USA

Keynote: J Membr Sci Technol

Abstract:

Research work on new nanostructured polymer-graphene hybrid coatings/membranes are presented with two major illustrated examples in energy and water-related applications (e.g., membrane separations of molecules/ions and high-performance supercapacitor electrodes). This work intends to develop the understanding to control the fundamental nanostructure of buildingblock graphene unit (i.e., stacked parallel graphene sheets of defined 2D dimension with precisely controlled interspacing by molecular spacers) as well as the architecture of the 3D graphene-polymer materials (i.e., the vertical orientation and connectivity of graphene units inside the polymer-bond hybrids). Several orders-of-magnitude performance enhancements (e.g., in molecular water permeability and ion transport) could be realized due to the well control of nanostructure and architecture of the synthesized hybrid interfacial materials. One key thrust for the functionalized porous inorganic membranes is to enable the use of larger nonzeolitic pores (>1 nm) for the greater permeation flux with enhanced surface selectivity for molecular separations. Specifically, the polybenzimidazole polymer and graphene oxide hybrid coating layers on porous metallic/ceramic tube supports have been developed and evaluated for biofuel thermochemical processing related separations such as dewatering of hydrothermal liquefaction (HTL) aqueous fractions for carbon (carboxylic acids) recovery and vapor-phase chemistry tailoring of the catalytic fast pyrolysis process. For supercapacitor electrode development, both nanosized dimension and vertical orientation of ligand functionalized graphene oxide sheet particles have demonstrated their significant effects on performance. The size control enhancement was more effectively achieved by ~4.2 times higher capacitance, 4.0 times lower IR drops and order of magnitude enhanced mass transport. Compared to the non-aligned counterparts, the coating containing vertically aligned graphene sheet particles have shown ~1.6 times higher values in capacitance (430 F/g at 0.5 A/g) and ~67% reduction in equivalent series resistance. Such hybrid materials are also being developed for other potential applications such as in batteries, desalination, and bioseparations processing. Recent Publications 1. G G Jang, B Song, L Li, J K Keum, Y Jiang, et al. (2017) Microscopic vertical alignment of nano-interspaced graphene architectures in deposit films as electrodes for enhanced supercapacitor performance. Nano Energy 32:88???95. 2. G G Jang, K-S Moon, C P Wong, J K Keum and M Z Hu (2017) Size-controlled, Aromatic amine ligand grafted graphene sheet deposit films for enhanced performance of supercapacitors. Carbon 119:296???304. 3. M Z Hu, C Engtrakul, B L Bischoff, et al. (2016) Superhydrophobic and superhydrophilic surface-enhanced separation performance of porous inorganic membranes for biomass-to-biofuel conversion applications. Sep. Sci. Technol. 1???16. 4. C Engtrakul, M Z Hu, B L Bischoff, et al. (2016) Surface-enhanced separation of water from hydrocarbons: potential dewatering membranes for the catalytic fast pyrolysis of pine biomass. Energy & Fuels 30:8483???8348.

Biography :

Michael Z Hu is a Chemical and Biochemical Engineer by education, serving as a Senior Research Staff Member at the Oak Ridge National Laboratory. Meanwhile, he is appointed by the University of Tennessee as a Joint Faculty Professor at the UT Bredesen Center and an Adjunct Professor at the Chemical & Biomolecular Engineering Department. He is the Founder Editor-in-Chief for the Journal of Nanomaterials. He has over 24 years of research experience in Advanced Nanomaterials and Chemical Processing Technologies for separations and catalysis. He is a Team Leader for the Department of Energy (DOE) program that won a 2014 R&D100 Award based on Advanced Nano-Membranes Research. His membrane technology development work became a success story in July 2017. He has been the Principal Investigator and also served as the Thermochemical Pathway Team Lead for a multi-lab separations consortium program addressing separation challenges related to processing of biofuels and bioproducts from biomass.

E-mail: hum1@ornl.gov