WO3 Nanorods/MXene composite as high performance electrode for supercapacitors

Tungsten oxide (WO3) as electrode material has the drawbacks including poor rate capability and low capacitance. We firstly report a facile strategy to prepare WO3/MXene composite by intimately electrostatic attraction between the positively charged WO3 nanorods (WNRs) and the negatively charged transition metal carbides (MXene). This type composite shows higher specific capacitance (297 F g−1) compared with pure WNRs (121 F g−1) at a current density of 1 A g−1 in 0.5 M H2SO4 aqueous electrolyte. In addition, the as-prepared composite electrode displays good retention rate (82.2% retention at 5 A g−1) and cyclic stability (73.4% even after 5000 cycles at 4 A g−1). The attractive electrochemical performance of WNRs/MXene may be attributed to the main reasons as follows: The MXene acts as electrons collector effectively improving the electrical conductivity and supplying more electrons to participate redox reactions happened on the surface and interior of WNRs; The electrostatic self-assembly improves the stability of WNRs/MXene.