Energy-storable dye-sensitized solar cells with improved charge/discharge performance

Dye-sensitized solar cells (DSSCs) are photoelectrochemical devices that can generate electricity in various light environments. To mitigate the inherent dependence of the DSSC output on the intermittent nature of Sun irradiation and to satisfy the ever-increasing demand for photovoltaic power generation, the development of high-performance energy-storable DSSCs that incorporate an energy-storage electrode similar to a rechargeable battery through a precise design of the electrochemical cell structure constitutes a promising approach. In this study, we constructed an energy-storable DSSC with improved photocharge/discharge characteristics by introducing a tungsten oxide-based charge-storage electrode and using photoelectrodes based on donor-pi-acceptor dyes having wide optical gap and a Br-/Br-3 (-) redox electrolyte. The as-prepared DSSC exhibited enhanced photocharge/discharge capacity and energy density and an increased open-circuit voltage to above 1 V, thus demonstrating its potential as an energy-storable DSSC for photovoltaic power generation for outdoor and indoor applications.