A Nonenzymatic Glucose Sensor Platform Based on Specific Recognition and Conductive Polymer-Decorated CuCo2O4 Carbon Nanofibers

CuCo2O4 decoration carbon nanofibers (CNFs) as an enzyme-free glucose sensor were fabricated via electrospinning technology and carbonization treatment. The CNFs with advantages of abundant nitrogen amounts, porosity, large surface area, and superior electrical conductivity were used as an ideal matrix for CuCo2O4 decoration. The resultant CuCo2O4–CNF hybrids possessed favorable properties of unique three-dimensional architecture and good crystallinity, accompanied by the CuCo2O4 nanoparticles uniformly growing on the CNF skeleton. To further enhance the selective molecular recognition capacity of the developed sensor, a conductive film was synthesized through the electropolymerization of thiophene and thiophene-3-boronic acid (TBA). Based on the synergistic effects of the performances of CNFs, CuCo2O4 nanoparticles, and boronic acid-decorated polythiophene layer, the obtained poly(thiophene-3-boronic acid) (PTBA)/CuCo2O4–CNF-modified electrodes (PTBA/CuCo2O4–CNFs/glassy carbon electrode (GCE)) displayed prominent electrocatalytic activity toward electro-oxidation of glucose. The fabricated sensor presented an outstanding performance in the two linear ranges of 0.01–0.5 mM and 0.5–1.5 mM, with high selectivity of 2932 and 708 μA·mM−1·cm−2, respectively. The composite nanofibers also possessed good stability, repeatability, and excellent anti-interference selectivity toward the common interferences. All these results demonstrate that the proposed composite nanofibers hold great potential in the application of constructing an enzyme-free glucose sensing platform.