Synergistic Effect of Bimetallic Ag and Ni Alloys on Each Other's Electrocatalysis to Glucose Oxidation

The electrocatalysis of Ag/Ni bimetallic alloys to glucose oxidation was studied. It was found that the presence of Ag and Ni in the alloys facilitates each other's electrocatalysis toward glucose oxidation, exhibiting an interesting synergistic effect. At about 0.7 V vs SCE, the electrocatalysis of Ag toward glucose oxidation was enhanced by Ni. However, it's very difficult to obtain stable response signals at this potential although a relatively large current response to glucose was observed. Similarly, the presence of Ag improved the Ni(OH) 2 /NiOOH mediated electrocatalytic oxidation of glucose at 0.45 V. By contrast, the Ag/Ni-deposited electrode responded rapidly to the changes of glucose concentration, producing stable signals within 4 s. Two linear ranges were identified with one at low glucose levels from 1 to 9.89 μM and the other at high glucose concentrations from 19.68 to 106.89 μM. The detection limit of the electrode is 0.49 μM. This study shows the potential to develop glucose based sensors or fuel cells.