Contribution of Ultrahigh Electrochemical Performance of NiCo2O4 Nanoneedle-Based Free-Standing Electrode from Functionalized Carbon Cloth

Abstract

Spinel structure NiCo2O4 suffers from poor electric conductivity and the resulted electrochemical properties in battery/supercapacitor system are still unsatisfied. In this paper, a free-standing electrode based on in-situ growth NiCo2O4 on carbon cloth has been synthesized by a surfactant-assisted solvothermal method (sodium dodecyl sulfate, SDS). The functional carbon cloth substrate makes unexpected contribution to the electrochemical lithium-ion storage. The assembled supercapacitor possesses ultrahigh pseudocapacitive properties with high mass loading. The specific capacitance of 2832[Formula: see text]F[Formula: see text]g[Formula: see text] has been obtained at 1[Formula: see text]A[Formula: see text]g[Formula: see text] current density with maintaining the high rate capability of 1620[Formula: see text]F[Formula: see text]g[Formula: see text] at 20[Formula: see text]A[Formula: see text]g[Formula: see text]. The obtained nanoneedle NiCo2O4/carbon cloth electrode also maintains a specific capacity of 2000[Formula: see text]mA[Formula: see text]h[Formula: see text]g[Formula: see text] at 40[Formula: see text]mA[Formula: see text]g[Formula: see text] and exceptional rate performance (1504[Formula: see text]mAh[Formula: see text]g[Formula: see text] at 400[Formula: see text]mA[Formula: see text]g[Formula: see text] when tested as anode material in lithium ion batteries.