Abstract: In order to enhance the dispersion of Fe₃O₄ nanoparticles in polymer electrolytes for dyesensitized solar cell (DSSC) applications, the ionic conductivity of the polymer electrolytes with different small molecular surfactants was studied. The surfactants used were polyethylene glycol (PEG₂₀₀), Triton X-100, acetyl acetone, and mixture of these three active agents at 1%(w) doping concentration of Fe₃O₄ nanoparticles in electrolyte. Comparison of the electrochemical properties of Fe₃O₄-doped polymer electrolytes containing different surfactants showed that PEG₂₀₀ was suitable for modifying Fe₃O₄ nanoparticles to disperse in agarose-based polymer electrolytes. When the mass fraction of PEG₂₀₀ was 61.8%(w), the electrolyte had excellent conductivity (2.88×10^-3 S·cm^-1). Electrochemical impedance spectra (EIS) revealed that when the concentration of PEG₂₀₀ increased, the electron lifetime and combination resistance of a dye-sensitized solar cell increase initially and then decreasd. The longest electron lifetime and the largest combination resistance were achieved when the concentration of PEG₂₀₀ was 68.3%(w).

Key words: Magnetical polymer electrolyte, Agarose, Nano-Fe₃O₄, PEG₂₀₀, Dye-sensitized solar cell