Dye-sensitized solar cells based on electrospun polyacrylonitrile (PAN) nanofibre membrane gel electrolyte

Abstract

Dye Sensitized Solar Cells (DSSCs) based on electrospun nanofibre membrane electrolytes offer several advantages over liquid electrolyte based solar cells. Nanofibre membranes having different thicknesses were prepared by electrospinning on platinum electrodes from a 11 wt% solution of polyacrylonitrile (PAN) in N,N-dimethylformamide (DMF) at an applied voltage of 8kV. The membranes were then activated by immersing in a solution containing potassium iodide (KI) (0.06g), propylene carbonate (PC) (0.8g) and iodine (I2) (0.0092g) for 30minutes to obtain “gel” type membrane electrolytes with different thicknesses. These nanofibre membrane electrolytes were used to fabricate quasi-solid state (gel) DSSCs and the performance of these solar cells were compared with DSSCs fabricated with liquid electrolyte (KI:PC:I2) and conventional PAN based gel electrolyte (PAN:KI:PC:I2). DSSC with nanofibre membrane electrolyte of thickness 9.14μm showed the highest light-to-electricity conversion efficiency of 5.2% whereas an identical cell based on corresponding liquid electrolyte showed an efficiency of 5.3%. The open circuit voltage (VOC), short circuit current density (JSc) and fill factor for the solar cell based on this electrolyte was 0.67V, 13.31mAcm−2 and 59% respectively at an incident light intensity of 1000Wm−2 with a 1.5 AM filter.