Preparation of Ni-Diamond-Like Composite Electrode and Its Application in Non-enzymatic Glucose Sensor

Nickel diamond-like (Ni-DLC) composite electrodes with different Ni contents were prepared on pure Ti substrate by high power pulsed magnetron sputtering technology, which was used to construct non-enzymatic glucose sensor. The surface morphology, microstructure and electrochemical performance of Ni-DLC composite electrode were characterized by X-ray diffractometer, atomic force microscope, Raman spectrometer and electrochemical workstation. The results show that: (1) with the increase of Ni content, the particle protrusion on the surface of Ni-DLC film increases gradually, and the diameter of agglomeration particles also increases, which significantly increases the active sites on the surface of Ni-DLC film. The content of sp2 bond in Ni-DLC film increases, the order degree of the film increases, and the conductivity of the film is improved. No obvious Ni-C bond is formed in the film, and Ni mainly exists in elemental form. (2) Glucose sensor made of Ni-DLC composite electrode was placed in glucose solution for testing. And the results show that Ni-DLC composite electrode has a good catalytic effect on glucose, electrode reaction is mainly controlled by diffusion, and oxidation peak current density and glucose concentration has a good linear relationship. Ni-DLC composite electrode for glucose detection sensitivity is 796 µA·(mmol/L)-1·cm-2, the lower limit of detection LOD=0.5 µmol/L, and the response time is 5 s. And the electrode has good anti-interference performance for uric acid and ascorbic acid. The electrode has a broad application prospect in the construction of non-enzymatic glucose sensor. © 2023 Rare Metals Materials and Engineering Press. All rights reserved.