Construction of NiTe/NiSe Composites on Ni Foam for High‐Performance Asymmetric Supercapacitor

NiTe/NiSe composites grown in situ on Ni foam are successfully developed as a binder‐free electrode for supercapacitors. The as‐obtained NiTe/NiSe composite electrode exhibits excellent electrochemical properties with a higher specific capacitance of 1868 F g −1 (5.60 F cm −2 ) at a current density of 1 A g −1 . In addition, an asymmetric supercapacitor is fabricated with NiTe/NiSe as the positive material and active carbon (AC) as the negative material. The resulting NiTe/NiSe//AC device exhibits a high energy density of 33.7 Wh kg −1 at a power density of 800 W kg −1 , providing good cycling performance that retained 86.2 % of the initial capacitance at 2 A g −1 after 5000 cycles. All of the results illustrate that the NiTe/NiSe electrode is promising for potential application in supercapacitors and other fields.