High-energy aqueous rechargeable batteries based on WSe2 nano-flower cathode

“Rocking-chair” zinc-ion batteries (ZIBs) are potential commercial energy storage devices because of their high energy density and safety. However, using appropriate cathode materials with weak polarization effect and tolerating the rapid insertion/extraction of zinc ions are still the huge challenges. Here, a WSe 2 nano-flower cathode material with hierarchical structure is successfully prepared by a facile solvent thermal strategy. The electrochemical data confirm that the WSe 2 cathode has high specific discharge capacity (545 mA h g −1 at 0.1 A g −1 ), excellent rate performance, and stable cyclic performance (81% after 100 cycles), which are superior to most reported electrode materials. The layered structure is beneficial to increase the specific surface area and conductivity of the electrode material and improve the battery discharge performance. This study opens new opportunities to promote the commercialization of rechargeable aqueous ZIBs.