Synthesis and Processing of Electroactive Polymers in Nanostructured Energy Devices

Drexel University, Philadelphia PA

Investigators

Abstract

PI: Lau, Kenneth K.S. Institutions: Drexel University Proposal Number: 1264487 Title: Synthesis and Processing of Electroactive Polymers in Nanostructured Energy Devices Energy storage is a key component in the energy conservation equation, especially when considering sustainable energies like solar and wind, which are more variable and intermittent in nature depending on the time of day, season of the year, and geographical location. Similarly, the ability to store energy and use it when demanded will provide a more seamless operation of electric vehicles whether during acceleration/deceleration or in cruise mode. Among different energy storage technologies, supercapacitors or electrochemical capacitors are emerging as an attractive option for delivering much higher power (rate of energy transfer) than alternative options like the lithium ion battery. Intellectual Merit Supercapacitors that store charge through electrochemical double layers possess higher power density but lack sufficient energy density. By incorporating electroactive polymers, which undergo relatively fast redox reactions, further pseudocapacitance can be added to enhance energy density. However, as the supercapacitor electrodes are typically highly porous nanostructures, there remains significant synthesis and processing challenges in adding the electroactive polymers onto the surfaces of pores inside these nanostructures without sacrificing surface area or pore access. The PI plans an oxidative chemical vapor deposition (oCVD) approach that will address many of the challenges by enabling the conformal, uniform growth of thin films of electroactive polymers inside porous nanostructured materials. The central hypothesis is that the liquid-free, vapor-to-solid polymerization reactions will lead to surface confined polymer growth and ultrathin films that do not significantly alter the underlying pore structure while adding appreciable pseudocapacitance. This work will involve (1) synthesis of electroactive polymer thin films in porous nanostructures, (2) understanding the effect of processing on polymer structure and properties, and (3) assembly and electrochemical analysis of pseudocapacitors that make use of oCVD to incorporate the electroactive polymers. Broader Impact This work is expected to deliver enhanced supercapacitors with significantly higher specific capacitance, energy density, power density and cycle stability, making them viable for use in electric and hybrid vehicles as well as in the development of greener energy systems that include solar cells and fuel cells. Fundamentally, the work is expected to provide an effective synthesis and processing methodology for conformally coating porous nanostructures that will have broader utility in other nanoscale devices, including electronics, sensors, solar cells, fuel cells, transistors and organic light-emitting diodes (OLEDs). Integrated with the research is an education program, which aims to train graduate and undergraduate students as well as to engage high school students in polymers for energy. Minority and underrepresented students will be actively recruited to participate in the project. In addition, outreach will be made to schools in Philadelphia and inner city Camden, NJ to promote STEM involvement and learning early on.