Composite of carbon nanomaterials and polyethylene oxide for dye sensitized solar cells

Various composite electrolytes were prepared by the mixing of carbon nanomaterials (carbon black, carbon nanotubes (CNTs) and carbon fibers (CFs)) and polyethylene oxide (PEO) for solid-state DSSCs. By morphological analysis, CF-PEO composite obtained the uniform coating and well penetration of PEO molecules on the surface of CFs. Among them, CF-PEO composite electrolyte exhibited the highest intensity of Raman shift, indicating the formation of I3⁻ ions in redox electrolyte. DSSC fabricated with CF-PEO achieved the high conversion efficiency of 4.94% with high short circuit current (JSC) of 10.5 mA/cm², open circuit voltage (VOC) of 0.730 V and fill factor (FF) of 64%. While, DSSCs with CB-PEO and CNT-PEO showed low conversion efficiencies of 2.9% and 4.15% respectively. The enhanced JSC and performance in CF-PEO is resulted from the high absorption of iodide couple and high ionic conductivity of CF-PEO composite electrolyte, resulting from the large amount of I3⁻ ions in redox electrolyte.