Highly Active Carbon Nanotube Supported Iridium, Copper, Ruthenium Catalysts for Glucose Electrooxidation

Abstract

Herein, carbon nanotube (CNT) supported ruthenium (Ru), iridium (Ir), and copper (Cu) catalysts at 0.1 to 20 wt% metal loading are prepared by the NaBH4 reduction method for glucose electrooxidation reaction (GER). These catalysts are successfully characterized by X-ray diffraction, scanning electron microscope, and N-2 adsorption-desorption measurements. Voltammetric measurements of these catalysts are taken using cyclic voltammetry and chronoamperometry techniques. The crystallite sizes of these catalysts are calculated as 2.53 nm for Ru/CNT, 2.94 nm for Ir/CNT, and 13.06 nm for Cu/CNT by using Scherrer equation. For GER, 10% Ru/CNT, 0.1% Ir/CNT, and 0.5% Cu/CNT catalysts have high current densities as 1.86 mA cm(-2) (160.6 mA mg(-1) Ru), 3.03 mA cm(-2) (23 857.2 mA mg(-1) Ir), and 1.12 mA cm(-2) (1768.8 mA mg(-1) Cu), respectively. These catalysts have also good stability. Results reveal that 10% Ru/CNT, 0.1% Ir/CNT, and 0.5% Cu/CNT catalysts are promising catalysts as direct glucose fuel cell anode catalysts.