Novel route to synthesis of N-doped graphene/Cu–Ni oxide composite for high electrochemical performance.

A facile and cost-effective one-pot solvothermal method has been successfully developed to synthesize an N-doped graphene (NG) and copper–nickel oxide (CuNiO) composite. The novel NG/CuNiO composite is proposed to be used as an electrode material for supercapacitors and non-enzymatic glucose sensors. Transmission electron microscopy images indicate the formation of CuNiO nanoparticles with an average diameter of approximately 5.6 nm, with good dispersion on the NG sheets. The composite exhibited an excellent specific capacity of ≈892 F g −1 (current density of 1 A g −1 ) and high long-cycle stability with a 98.5% retention in specific capacitance after 5000 cycles at a current density of 5 A g −1 . This superior electrochemical performance is attributed to high charge mobility, the flexibility of the N-doped graphene structure, and the synergetic effect between CuNiO nanoparticles and NG sheets. Further, the proposed sensor exhibited rapid response (<10 s), high sensitivity (7.49 μA mM −1 cm −2 ), a wide detection range (0.2 μM–0.3 mM), good reproducibility, long-term stability, and a low detection limit 50 nM ( S / N = 3). The NG/CuNiO composite electrode can be used for high performance supercapacitor and non-enzymatic glucose sensor applications. [ABSTRACT FROM AUTHOR]