Tailor-designed Pd-Cu-Ni/rGO nanocomposite for efficient glucose electro-oxidation

Abstract

• Pd-Cu-Ni/rGO shows a striking activity towards GOR. • Capacitance measurements explain the observed enhancement. • Smart design of the catalyst increases the fuel utilization and turnover frequency values. • Pd-Cu-Ni/rGO/GC shows high sensitivity and selectivity towards GOR. The study presented in this paper introduces a promising ternary catalyst composed of palladium-copper-nickel nanocomposite which is electro-deposited at reduced graphene oxide modified glass carbon electrode (Pd-Cu-Ni/rGO/GC). The modified electrode is shown to exhibit an excellent activity towards glucose electrooxidation reaction (GOR), where the peak current obtained at its surface is 4.6, 3.0, 2.2 times of that achieved at Cu/rGO/GC, Ni/rGO/GC, and Pd/rGO/GC electrodes, respectively. Additionally, Pd-Cu-Ni/rGO/GC electrode exhibits a high capacitance, a long-term stability, besides supporting a high oxidation capacity and a high turnover frequency for GOR. Moreover, Pd-Cu-Ni/rGO/GC electrode exhibits a great sensitivity of 2800 µA mM −1 cm −2 to GOR with detection limit of 0.01 µM using a signal-to-noise ratio value of 3, it also has a high molecular selectivity for GOR. rGO is believed to augment the surface area, durability, and electrical properties of the catalyst. Pd provides the active sites and NiOx acts as a catalytic mediators for GOR. CuOx has a narrow band gap suitable for glucose sensing applications.