Oxidative and Initiated Chemical Vapor Deposition of Polymer Electronic Materials for Applications in Energy Conversion and Storage

Initiated and oxidative chemical vapor deposition (iCVD/oCVD) are novel surface polymerization techniques for the formation of polymer thin films. Taking advantage of a vacuum environment, polymer CVD enables the synthesis of stoichiometric polymers that can be applied on different surface geometries down to nanometer scale. In iCVD and oCVD, the surface adsorption of reactive species is typically the limiting step, which means the polymer growth and properties can be tuned by adjusting the surface availability of the reactants. In this work, iCVD and oCVD were utilized for the synthesis and integration of electronic polymer materials in the nanostructured electrodes of energy conversion and storage devices. iCVD was used to synthesize poly(2-hydroxyethyl methacrylate) (PHEMA) as a potential polymer electrolyte while oCVD was used to make unsubstituted polythiophene (PTh) as a potential electrically conducting polymer. PHEMA was then integrated within the mesoporous electrode of dye sensitized solar cells and iCVD conditions that enabled successful pore filling were identified. The resulting devices fabricated with iCVD PHEMA polymer electrolyte showed superior performance when compared to their liquid counterparts. PTh was integrated in the porous electrode of activated carbon supercapacitors and oCVD conditions that enabled conformal ultrathin coating were found. The resulting devices with oCVD PTh was found to have significantly higher charge storage capacity as a result of the synergistic effect of the redox polymer and the nanostructured topology. Overall, this work demonstrated the viability of iCVD and oCVD pathways for the design, synthesis, and processing of polymers in nanostructured architectures for energy applications. Success ultimately depended on a clear understanding of the fundamental kinetic and transport mechanisms for enabling polymer integration.Ph.D., Chemical Engineering -- Drexel University, 201