Enhancing the open circuit voltage of dye sensitized solar cells by surface engineering of silica particles in a gel electrolyte
We prepared a quasi-solid electrolyte for dye-sensitized solar cells (DSSCs) that consist of ionic liquid and modified silica particles. Commercial bare silica F5 particles and modified silica F5 by NH2 and NH3+ groups were prepared, and fully characterized. The best photovoltaic performance was observed using the NH2 modified silica particles giving an open circuit voltage (V-oc) of 815 mV, a short-circuit current (J(sc)) of 11.23 mA cm(-2), and a fill factor (FF) of 0.75 corresponding to an overall power conversion efficiency of 7.04% at 100 mW cm(-2) AM 1.5. The modification of the silica particles by NH2 groups increases the V-oc of DSSCs by around 60 mV compared to pure ionic liquid electrolyte based DSSCs.