Ultrafine SnO 2 in situ modified graphite felt derived from metal–organic framework as a superior electrode for vanadium redox flow battery

Abstract Metal–organic framework (MOF) and its derivatives have low‐cost, controllable structure, and good catalytic performance, which are often used in the electrochemical field. In this work, SnO 2 in situ modified graphite felt (SnO 2 /GF) is prepared by hydrothermal method then simple thermal treatment using Sn‐based MOF (Sn‐MOF) as precursor. SnO 2 is uniformly and firmly distributed on the GF surface rather than the common agglomeration and poor bonding of metal oxides on carbon‐based electrodes, providing stable active centers for the VO 2+ /VO 2 + and V 2+ /V 3+ redox reactions. At 250 mA·cm −2 , the energy efficiency of the battery with SnO 2 /GF remains at 63.2%, while the blank one has failed. The former battery, at 100 mA·cm −2 , has higher energy efficiency and good cycle stability (over 200 cycles). The battery performance of this study is better than that of most previous report in metal oxide‐related work. This work obtains high‐performance composite electrode by simple treatment of MOF, which provides a reference for the application of MOF in vanadium redox flow battery.