Effect of Pt-Ni deposition sequence on the bimetal-modified boron-doped diamond on catalytic performance for glucose oxidation in neutral media

Abstract

• The PtNi modified boron-doped diamond were fabricated to detect glucose at neutral pH. • Electrodeposition sequences effect on electrocatalytic properties of Pt-Ni bimetals. • The PtNi biemetal prepared by co-deposition had the highest stability and sensitivity. The growing number of people with diabetes has gained extensive attention over the past decades, driving the need to develop sensitive glucose sensors to monitor glucose levels under physiological pH conditions. Bi-metal (Pt-Ni) modified boron-doped diamond (BDD) electrodes were reported to allow a continuous and stable response measurement of glucose under neutral pH conditions. Effects of the electrochemical deposition sequence on the morphology and electrocatalytic properties of the Pt-Ni bimetal were systematically investigated. Electrochemical tests showed that the Pt-Ni bimetal clusters prepared by the co-deposition (one step) method had higher stability and sensitivity for the glucose detection than those prepared by the two-step deposition method. The PtNi-BDD increased around 19% of the initial signal after 200 consecutive cyclic voltammetry cycles for 2400 s, while as a comparison, Ni/Pt-BDD and Pt-BDD increased 44% and 40% for 2400 s, respectively. In addition, the sensitivity of PtNi-BDD was obtained to be 110.4 μA cm −1 mm −1 in the range of 2–12 mM glucose concentration, around 6.1, 15.5, and 6.0 times higher than that of Pt/Ni-BDD, Ni/Pt-BDD, and single metal Pt, respectively.