Preparation of TiO2 paste using poly(vinylpyrrolidone) for dye sensitized solar cells

The surface morphology of titanium oxide (TiO2) films as a photoanode in dye sensitized solar cells plays a vital role in converting light to electricity. Therefore, TiO2 films were prepared using TiO2 paste with different compositions of poly(vinylpyrrolidone) (PVP) as a binder to optimize their physico-chemical properties. The paste was prepared with commercial TiO2 powder mixed with acetylacetone, PVP, 4-octylphenol polyethoxylate, acetic acid and ethanol. The chemical composition remains the same for all pastes except PVP. The quantity of the PVP was optimized in such a way that it provides a thick film with a good network connection. The impact of the quantity of PVP in the TiO2 paste was analyzed. The prepared TiO2 film structure was characterized by X-ray diffraction. The surface morphology was analyzed by scanning electron microscopy. The electrochemical performance of the prepared TiO2 as a photoanode was also investigated. Among the four different photoanodes, the cells fabricated with a TiO2 film prepared with 0.4 g of PVP exhibited the highest power conversion efficiency of 6.77%, short-circuit photocurrent density and open circuit voltage of 12.38 mA/cm2 and 0.77 V, respectively.

► TiO2 pastes using poly(vinylpyrrolidone) (PVP) for dye sensitized solar cell (DSSC)
► PVP used in the paste increases the viscosity and adhesion of the TiO2 paste.
► Varying PVP contents in the paste with constant TiO2 affected DSSC performance.
► This reveals the importance of paste composition for better DSSC performance.