Double Fence Porphyrins Featuring Indacenodithiophene Group as an Effective Donor for High-Efficiency Dye-Sensitized Solar Cells

Porphyrins are an important category of dyes for efficient dye-sensitized solar cells (DSSCs). However, the efficiency improvement of DSSCs lags behind those of organic and perovskite solar cells owing to deficiencies in new design strategies of dye molecular structures. Recently, double fence porphyrins with superior photovoltaic performance were reported, in which eight alkoxyl chains were introduced to wrap the porphyrin core and retard the approach of the electrolyte to the surface of TiO2. On the basis of the design strategy of double fence porphyrins, novel porphyrins bJS8, YS2, YS3, YS7, and MC1 featuring dual functional indacenodithiophene group are synthesized and their photovoltaic performance in DSSCs are studied. Among these new double fence porphyrin dyes, YS7 exhibits an improved power conversion efficiency of 11.4% (short circuit photocurrent (J(SC)) = 17.34 mA cm(-2), open circuit photovoltage (V-OC) = 0.864 V, and fill factor (FF) = 0.758) compared to the previously reported double fence porphyrin bJS2 of 10.7% (J(SC) = 16.59 mA cm(-2), V-OC = 0.849 V, and FF = 0.759) and the benchmark porphyrin dye GY50 of 10.1% (J(SC) = 16.14 mA cm(-2), V-OC = 0.863 V, and FF = 0.725) under optimized conditions, providing a new molecular design strategy for high-efficiency porphyrin dyes in DSSCs.