Position: Ph.D. Candidate

Current Institution: University of California, Berkeley

Polymer Nanocomposite Dielectric Materials for Energy Storage Applications

Materials with high dielectric constants have drawn increasing interests in recent years for their important applications in capacitors, actuators, and high energy density pulsed-power. Particularly, polymer-based dielectrics, owing to their properties like high electric breakdown field, low dielectric loss, flexibility and easy processing are excellent candidates. In order to enhance the dielectric constant of polymer materials, high dielectric constant fillers materials are added to the polymer. Typically, the dispersion of nanoparticles in polymer matrices is problematic and the nanoparticles tend to phase separate or aggregate in the polymer matrix.

We propose the use of metal nanoparticle fillers to enhance the dielectric properties of the base polymer while minimizing dielectric loss by preventing nanoparticle agglomeration. Novel combinations of materials, which use 5 nm diameter metal nanoparticles embedded inside high breakdown strength polymer materials are evaluated. High breakdown strength polymer materials are chosen to allow further exploration of these materials for energy storage applications. The focus is on obtaining a uniform dispersion of nanoparticles with no agglomeration by utilizing appropriate ligands/surface functionalizations on the gold nanoparticle surface. Use of ligand coated metal nanoparticles will enhance the dielectric constant while minimizing dielectric loss, even with the particles closely packed in the polymer matrix.

The developed nanocomposite system consists of polyvinylpyrrolidone (PVP) functionalized gold nanoparticles embedded inside a polvinylidene fluoride (PVDF) polymer matrix. A homogeneous dispersion of gold nanoparticles with low particle agglomeration has been achieved upto 15 wt% of nanoparticles. Dielectric characterization of the nanocomposite material with 10 wt% nanoparticle content showed a 2x enhancement in the dielectric constant over the base polymer and low dielectric loss values were observed. A photodefinable nanocomposite dielectric is also developed using the SU-8 polymer.

I am a Ph.D. candidate majoring in Nanotechnology at University of California, Berkeley. I am advised by Prof. Albert Pisano and Prof. Tarek Zohdi. I also collaborate closely with Prof. Thomas Russell, Lawrence Berkeley National Lab. My research interests include dielectrics, nanocomposites, self-assembly of nanomaterials, energy storage, and conversion.

The focus of my work has been on developing advanced functional materials for applications in the field of energy storage. I have worked on the development of polymer nanocomposites based solid-state dielectric materials. I am currently working on the generation of structured fluids that would enable novel applications such as an all-liquid battery which offers very high ion transport and low impedance.

During graduate training, I got the opportunity of student interaction through teaching and research advising. I have taught and mentored students in my role as Teaching Assistant for two undergraduate courses at Berkeley. I have been proactive in managing extra-curricular events and serving as a liaison for several graduate student events. I have run a weekly Nanotechnology colloquium event for the past three years that hosts speakers from both academic backgrounds and industrial labs. I am also a member of EECS graduate women association (WICSE).

I completed MS in EECS, UC Berkeley in 2015 and B.E. in Manufacturing Processes and Automation Engineering in 2010 from University of Delhi, India. During undergraduate study, I worked on a variety of projects, involving design, fabrication and mathematical analysis of automated material handling systems. I also worked at Bharat Heavy Electricals Limited (BHEL), India on the design of fire protection system layouts for thermal power plants from 2010-2011.