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In 2000, He et al. reported that the combination of a NiO-based photoactive cathode with a TiO2-based photoanode produced a tandem device with an open-circuit voltage (VOC) of 0.73 V,[1] which is the sum of the open-circuit potentials of the separate devices, where the TiO2-based electrode contributed 0.65 V and the NiO-based electrode 0.08 V. Tandem dye-sensitized solar cells (TDSCs), such as He s, have suffered from the lack of research directed at the optimization of the photocathode, despite the potential they hold in developing higher voltage devices. Only recently have researchers begun to address issues associated with NiO-based DSCs, such as low short-circuit photocurrents (JSC) and poor fill factors (FF).[2–6] We present herein a three-fold increase in VOC(0.35 V), while maintaining a JSC of 1.7 mA cmÀ2, for a p-type NiO dye-sensitized solar cell (p-DSC) employing a carefully designed “dyad …