A novel TiSe2 (de)intercalation type anode for aqueous zinc-based energy storage

Abstract

Rechargeable zinc-based aqueous system is attractive for energy storage technology due to its safety, low cost, and ecological friendliness. However, the growth of Zn dendrites in anode severely limits the development of the energy storage system. Here, TiSe2 is verified as an intercalated anode for aqueous zinc ion batteries (ZIBs) and zinc ion hybrid supercapacitors (ZHSCs) by a series of experimental and theoretical studies. The interlayer spacing of 0.601 nm makes TiSe2 suitable for (de)intercalation of zinc ions and its good electronic conductivity endows TiSe2 with excellent electrical charge transport characteristics. The TiSe2 electrode shows a capacity of 128.0 mA h g−1 at 0.20 A g−1, low working potential window (0.00–0.60 V vs Zn2+/Zn), and a recyclability of 70.0% retention after 300 cycles. Fabricated by TiSe2 anode and VO2 cathode, an aqueous ZIBs is successfully demonstrated, delivering a capacity of 44.3 mA h g−1 at 0.20 A g−1. Fabricated by TiSe2 anode and activated carbon (AC) cathode, a ZHSC is demonstrated with a specific capacitance of 60.6 F g−1 at 0.20 A g−1. This work brings an attempt and exploration of electrode materials about a (de)intercalation battery-type anode instead of Zn metal anode for aqueous ZIBs and ZHSCs.