The conventional dye sensitized solar cell (DSSC) is limited by the use of a liquid electrolyte that is prone to leakage and evaporation. Efforts to replace the liquid with a solid equivalent have been met with difficulties in penetrating the mesoporous TiO2 nanostructured photoanode with liquid processing, particularly for photoanode layer thickness greater than 2 μm. Here, initiated chemical vapor deposition (iCVD) is successfully applied to directly synthesize and fill the pores of the mesoporous TiO2 network of up to 12 μm thickness with poly(2-hydroxyethyl methacrylate) (PHEMA) polymer electrolyte. Comparing with equivalent liquid electrolyte cells, DSSCs integrated with PHEMA polymer electrolyte showed consistently higher open circuit voltage, which is attributed to a decrease in electron recombination with the redox couple at the electrode-electrolyte interface.

Pulsed plasma enhanced chemical vapor deposition films have been grown from C2H2F4, CH2F2, and CHCLF2. C-Is x-ray photoelectron spectroscopy (XPS) indicates a prevalence of C-CF species in the films from C2H2F4 and CH2F2, whereas CF2 species dominate the films from CHC1F2. The CFx species distributions for the films are largely controlled by the competition between CF2-producing and HF elimination reactions in the pulsed plasmas. Dominance by HF elimination produces films with high C-CF and CF concentrations (e.g., CH2F2), whereas dominance by CF2-producing reactions leads to films with higher CF2 concentrations (e.g., CHCIF2). The % CF3 in the film is lowest for the precursor having the lowest F:H ratio, CH2F2. Little or no hydrogen was detected in the deposited films. Thermal degradation of films from C2H2F4 and CH2F2, as probed by solid-state nuclear magnetic resonance (NMR) spectroscopy, shows a loss through CF3 detachment and HF elimination. Pulsed plasma films from all three precursors gave dielectric constants of 2.4, with loss tangents on the order of 10−2. Dielectric measurements of pulsed plasma films from hexafluoropropylene oxide (HFPO) gave a dielectric constant of 2.0 ± 0.1 with a loss tangent of 0.009.