Solar energy conversion, storage, and release using an integrated solar-driven redox flow battery
We have conceptualized and demonstrated a device that combines the functions of a solar photovoltaic cell and a redox flow battery, which we call the solar flow battery (SFB). Our lab-scale device is based on a crystalline n-WSe2 light absorber, carbon auxiliary electrodes, an iodide positive electrolyte, and an anthraquinone sulfonate negative electrolyte. We have designed a two-compartment flow cell and used it to independently characterize the electrochemical properties of the electrolytes, the photoelectrochemical properties of the n-WSe2 absorber, and the charge–discharge performance of the full SFB. Our WSe2-based SFB is as simple to construct as a water-splitting photoanode assembly, but it exhibits markedly higher energy conversion efficiency and also accommodates time-shifted recovery of the stored energy as electricity.