(4bh) Hierarchical Nanostructured Electrodes for Efficient Electrochemical Energy Storage Devices

Next generations electrochemical energy storage devices for hybrid or plug-in-hybrid vehicles would require both high-power, high-energy density with lower emission for sustainability. To achieve the goals, it is essential to identify novel electrode materials that can accommodate efficient transport ions and electrons in addition to high surface area. Energy storage devices based on based on nanoscale materials (nanoparticles, nanotubes or nanofibers of electroactive polymers, metal oxides and carbon nanotubes) recently gained significant interest to afford high-power, high-energy density without compromising cycle life.  During my postdoctoral research at MIT, I’ve developed expertise in the design of novel electrode assembly for energy storage devices. I focused on developing hybrid electrodes based on conjugated polymers (Polyaniline, PANi), metal oxides (TiO₂) and multi-walled carbon nanotubes (MWNT); these nanostructured hybrid electrodes performed exceptionally well (compared to graphitic electrodes) delivering high-power, high-capacity simultaneously for electrochemical pseudocapacitors that  suitable for electric vehicles or plug-in electric vehicles.  Along with conventional electrode development, I designed alternative layer-by-layer assembled electrodes based on electrostatic interaction of nanomaterials. The electrode architecture, assembly technique and post treatment were optimized to create high performance films. These electrodes were engineered to achieve high electronic conductivity and high porosity for improved ion transport of aqueous or organic electrolytes rendering higher capacitance than graphite electrodes with excellent mechanical and electrochemical stability over thousands of cycles. The development of hybrid electrodes of MWNTs and PANi nanofibers with controlled aspect ratio and morphology exhibits attractive potential in terms of improved electronic conductivity and porosity that are competitive with state-of-the-art RuO₂. However, these multilayer electrodes of nanoscale materials would reach a performance limit unless we optimize the electrolytes that can severely affect ion conduction and thereby overall electrochemical performance. Polymer-based gel electrolyte could a solution to address the challenge that could be part of the separator membrane in the overall electrochemical cell design. My Ph.D research expertise on polymeric membrane design and manufacturing at the University of Waterloo would allow me to develop such novel separator membranes.  

In future, as an independent researcher, I would like to focus on developing hierarchical nanostructured electrodes and electrolytes for the fundamental study and development of energy storage and conversion technologies. The novel electrode materials along with the gel electrolyte have tremendous potential to impact the electrode architecture and performance for high performance energy storage devices like metal-air batteries and pseudocapacitors. I will apply the expertise and ideas of nanomaterial synthesis, self-assembly, structure-property-processing of materials electrochemistry and the study of electronic and ionic interactions to create efficient and robust energy storage device for a sustainable environment.