CALM TALK 168 | From Stabilized Coacervates to Enhanced Energy Storage in 2D Nanofilled Polymer Films to Mxene-Go Membranes

主题：CALM TALK 168 | From Stabilized Coacervates to Enhanced Energy Storage in 2D Nanofilled Polymer Films to Mxene-Go Membra 主讲人：Alamgir Karim 教授 时间：2024-06-15 10:00:00 地点：松江校区复材大楼A212学术交流室 组织单位：先进低维材料中心 报告人简介：Alamgir Karim Dow and Welch Chair Professor, and Director of MaterialsEngineering Program and Director of Polymer and Soft Matter Center atUniversity of Houston. He obtained his Ph.D. in Physics fromNorthwestern University and post-doc in Chemical Engineering at University ofMinnesota. He was Group Leader of Polymer Blends, Combinatorial Methods andNanomaterials Group at NIST. He became Goodyear Chair Professor of PolymerEngineering, and Co-Director, Akron Functional Materials Center at Universityof Akron, and was Associate Dean of Research and Institute Director. His areas of interest and research includepolymer thin films, surfaces and interfaces and nanocomposites for energy andsustainability. He is a Fellow of the American Physical Society (APS),Fellow of American Association for the Advancement of Science (AAAS), and Fellowof Neutron Scattering Society of America (NSSA).报告摘要：The talk will cover research summaries in threeareas under investigation in our group. 1) Stabilized and E-Field DrivenPolymer Coacervates: Many of the unique properties of biological materials arederived from the highly charged nature of the constituent molecules and theirdiffuse counterion clouds, which often render such materials intrinsicallypolarizable, and thus highly responsive to electric fields. We investigate asynthetic material of this kind created through the formation ofpolyelectrolyte coacervates transferred to distilled water to extract excesscounterions to form highly stable droplet suspensions in which individualdroplets, and their large configurations, can be precisely manipulated withfield strengths comparable in magnitude to a 9-volt battery. These materialsshould be useful in encapsulating, transporting, and delivering various cargosin numerous applications in manufacturing and medicine and as a model systemfor understanding electrodynamic aspects of living systems. 2) Energy Storagein Ultrathin and 2D Nanofiller Polymer Film Systems: Ultrathin polymer filmspresent unique opportunities to understand the physics and properties ofpolymers at the nanoscale when the film thicknesses become comparable to thepolymer dimensions. We demonstrate that ultrathin glassy polymer (PMMA) films(~100 nm) that exhibit an order of magnitude higher dielectric strength (EBD)and capacitive energy density (Umax ∝ EBD2) of ~27 J/cm3 as compared to the bulk polymerfilms when used as dielectric capacitors. Further, polymer thin filmheterostructure based capacitor of poly(vinylidene fluoride)/poly(methylmethacrylate) with stratified 2D nanofillers (Mica or h-BN nanosheets)(PVDF/PMMA-2D fillers/PVDF) shows an ultrahigh energy density of ≈75 J/cm3 withefficiency over 79%. 3) 2D GO-MXene Membranes for Dye and Salt Separations:Membrane-based water purification is poised to play an important role intackling the potable water crisis for safe and clean water access for thegeneral population. Several studies have focused on near two-dimensionalmembranes for this purpose, which is based on an ion rejection technique.However, membrane swelling in these materials has emerged as a significantchallenge because it leads to the loss of function. Herein, we report aself-cross-linked MXene-intercalated graphene oxide (GO) membrane that retainsion and dye rejection properties because the physical cross-linking interactionbetween Ti–O–Tiand neighboring nanosheets effectively suppresses the swelling of the membrane. 视频： 摄影： 撰写： 信息员：张妮 编辑：高坤