(378x) CZTS (Cu2ZnSnS4) Electrode for Solar Rechargeable Polysulfide Bromide Redox Flow Battery

The increased dependency on solar energy requires large scale energy storage system as the source is often intermittent. Redox Flow Batteries (RFB) are very successful at storing the large amount of energy in a cost effective, safe and efficient environment. We took a unique approach for simultaneous solar energy conversion and storage by introducing a K doped CZTS (Cu₂ZnZnS₄: K) photo electrode in a polysulfide-bromide RFB. The photo-assisted reduction of polysulfide generating stable ~ 0.3 mA/cm² photocurrent corresponds to the charging of the battery. The usage of the same electrode to discharge the battery eliminated the need for an additional electrode. The catalytic effect of Cu⁺ has been exploited for improving electrochemical performance of the electrode.