Quasi-solid-state dye-sensitized solar cells employing ternary component polymer-gel electrolytes

Ternary component polymer-gel electrolytes are designed to facilitate ion transport in a highly viscous medium and utilize incident light more efficiently in dye-sensitized solar cells (DSSCs). Polyethers with multiple molecular size distributions are employed as solvents and TiO2 nanoparticles as a filler to prepare the polymer-gel electrolytes. The ion transport properties of the electrolytes are systematically investigated using electrochemical analyses such as ion conductivity and diffusion coefficient measurements. The influences of the electrolyte components on the electron transport in photoanodes are also investigated by measuring the laser-induced photovoltage and photocurrent transient response, incident photon-to-current efficiency (IPCE), and current–voltage (J–V) curves. The optimized polymer-gel electrolyte results in greatly enhanced energy conversion efficiency (i.e., 7.2% at 1 sun) due to the significantly improved ion transport and good light-scattering effect of the nanofillers.