In situ TiO2 decorated carbon paper as negative electrode for vanadium redox battery

Developing high-performance electrode is crucial to energy storage performance of vanadium redox battery. Herein, TiO2 decorated carbon paper was developed by hydrothermal route with various treatment time, and employed as negative electrode for vanadium redox battery. TiO2 can be in situ covered on carbon paper by hydrothermal route. Wetting performance of carbon paper is markedly enhanced by introduction of TiO2. Compared with raw carbon paper, TiO2 decorated carbon paper demonstrates excellent electrochemical performance towards V3+/V2+ couple. The sample treated for 6 h (CP-H06) exhibits the best electrochemical properties. The enhanced performance comes from the accelerated transfer of vanadium ions and electrons. The single cell testing indicates that the cell performances are improved significantly by using CP-H06 as negative electrode in terms of increased discharge capacity and energy efficiency. Discharge capacity and energy efficiency increase by 17.8% and 6.4% by using CP-H06 at 100 mA cm−2, respectively. Our study reveals that TiO2 decorated carbon paper with outstanding electrochemical performance exhibits a promising prospect in the energy storage system of vanadium redox battery.