Amorphous Zinc Stannate (Zn₂SnO₄) Nanofibers Networks as Photoelectrodes for Organic Dye‐Sensitized Solar Cells

Abstract

Abstract A new strategy for developing dye‐sensitised solar cells (DSSCs) by combining thin porous zinc tin oxide (Zn 2 SnO 4 ) fiber‐based photoelectrodes with purely organic sensitizers is presented. The preparation of highly porous Zn 2 SnO 4 electrodes, which show high specific surface area up to 124 m 2 /g using electrospinning techniques, is reported. The synthesis of a new organic donor‐conjugate‐acceptor (D‐π‐A) structured orange organic dye with molar extinction coefficient of 44 600 M −1 cm −1 is also presented. This dye and two other reference dyes, one organic and a ruthenium complex, are employed for the fabrication of Zn 2 SnO 4 fiber‐based DSSCs. Remarkably, organic dye‐sensitized DSSCs displayed significantly improved performance compared to the ruthenium complex sensitized DSSCs. The devices based on a 3 μm‐thick Zn 2 SnO 4 electrode using the new sensitizer in conjunction with a liquid electrolyte show promising photovoltaic conversion up to 3.7% under standard AM 1.5G sunlight (100 mW cm −2 ). This result ranks among the highest reported for devices using ternary metal oxide electrodes.