Abstract
Solid-state dye-sensitized solar cells were fabricated with solid polymer electrolyte consisting of I-/I3- redox couple supporting electrolyte and a hyper-branched graft copolymers of poly(methyl methacrylate-co-chloromethlystyrene )-g-poly[(oxy-ethylene)9 methacrylate] (PMMA-g-POEM9) synthesized by atom transfer radical polymerization (ATRP). The photoelectrochemical performances shows the low efficiency for energy conversion, in comparison to the cells with liquid electrolytes, due to the reduced mobility of I-/I3- in polymer electrolyte and the poor electric contact between polyelectrolyte and porous thin film electrode. For the improvement of the performance, the use of polyethyleneglycole (PEG) solution and heating treatments of solar cells were examined. On the Dye-sensitized solar cells (DSSCs) improved these methods, the short circuit current density and the open circuit voltage obtained for an incident light intensity of 110 mW cm^·2 were uplifted to 0.571 mA cm^·2 and 0.599 V, respectively. This corresponds to an overall efficiency to electric energy conversion efficiency and fill factor of 0.228 % and 0. 734, respectively.
