One-step synthesis of 2D vertically-aligned hybrid CuSe@NiSe nanosheets for high performance flexible supercapacitors

An in-situ one-step hydrothermal method is used to prepare hybrid CuSe@NiSe nanosheets with vertical orientation and interpenetrating structure on the surface of copper foam (S-CuSe@NiSe). The S-CuSe@NiSe has excellent electrochemical performance and outstanding cycling performance. The specific capacitance of the S-CuSe@NiSe is 1478 F g -1 at a current density of 1 A g -1 and stabilizes at 990 F g -1 at 8 A g -1 . The specific capacitance retention of S-CuSe@NiSe is 81.7% after 10,000 cycles. The all-solid-state flexible capacitors prepared with S-CuSe@NiSe as electrode (S-CuSe@NiSe-SFCs) also exhibit excellent flexibility, superior electrochemical performance and cycle stability. Its capacitance reaches 333 F g -1 at a current density of 1 A g -1 . Capacitance retention of 79.3% has been obtained after 10,000 charge-discharge cycles at 2 A g -1 .