Electrospun Microfibrous Membranes with Atmospheric-Pressure Plasma Surface Modification for the Application in Dye-Sensitized Solar Cells

Electrospun poly(vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP) microfibrous membrane was modified by cyclonic atmospheric-pressure plasma in this work. The gas-phase temperature of plasma state was <90 degrees C, indicating that this plasma could treat electrospun PVDF-HFP membrane without heat damages. Surface properties of the plasma-modified electrospun PVDF-HFP membranes were examined by the static contact angle (CA) analysis. It was observed that such cyclonic atmospheric-pressure plasma was useful in electrospun PVDF-HFP membrane surface modification; for example, the water CA was reduced from 137 to <30 degrees with only 1min treatment time. Field-emission scanning electron microscopy was used to determine the changes in surface features of the electrospun PVDF-HFP membrane after plasma treatment. A dye-sensitized solar cell (DSSC) fabricated with the plasma-modified electrospun PVDF-HFP membrane electrolyte revealed good conversion efficiency. This work proved that surface modification of the electrospun PVDF-HFP microfibrous membrane by cyclonic atmospheric-pressure plasma was an innovative method for DSSC applications.