Synergistic effect of metal ion additives on graphitic carbon nitride nanosheet-templated electrodeposition of Cu@CuO for enzyme-free glucose detection

Graphitic carbon nitride nanosheets (g-C3N4 NS) were prepared and used for self-templated electrodeposition of copper and copper oxide nanostructures. The as-prepared g-C3N4 NS can provide a lot of anchoring sites for copper ions in the process of electrodeposition. The electrodeposited CuO@Cu demonstrates high density and good uniformity. During the electrodeposition, the addition of nickel ions had enabled to entrap Ni ions in the lattice of CuO. The CeO2-CuO@Cu/g-C3N4 NS composites have been prepared by the addition of Ce ions in the process of electrodepositing CuO@Cu onto g-C3N4 NS. The cerium and nickel ions, as the additives, can effectively improve the density and uniformity of the electrodeposited CuO@Cu. Furthermore, the successful entrapment of CeO2 and Ni ions greatly improve electrochemical performance of CuO@Cu/g-C3N4 NS/ITO in the non-enzymatic detection of glucose. The Ce and Ni ion additives showed a synergistic effect on improving uniformity and density of the electrodeposited CuO@Cu and electro-catalytic properties of as-prepared composites. The as-prepared CuO@Cu/g-C3N4 NS/ITO, CeO2-CuO@Cu/g-C3N4 NS/ITO and Ni-doped CuO@Cu/g-C3N4 NS/ITO have been respectively used for non-enzymatic detection of glucose. These three proposed electrodes all demonstrate good electrochemical performance in the non-enzymatic detection of glucose. The CeO2−CuO@Cu/g-C3N4 NS/ITO and Ni-doped CuO@Cu/g-C3N4 NS/ITO appear to greatly improve the electro-catalytic activity toward the oxidation of glucose. Among these three electrodes, the Ni-doped CuO@Cu/g-C3N4 NS/ITO demonstrated the best electrochemical performance in the detection of glucose. These three proposed electrodes all demonstrated good stability and anti-interference performance.