Novel nonenzymatic hydrogen peroxide sensor based on iron oxide-silver hybrid submicrospheres.

Fe(3)O(4)-Ag hybrid submicrosphere was synthesized and developed as hydrogen peroxide sensor in this study. The hybrid sphere was fabricated via a two-step route, and proved by characterizations such as TEM, SEM, EDX, and XPS. Recent studies of hydrogen peroxide sensor based on silver nanoparticles inspired us to study the electrocatalytic property of the as-prepared submicrosphere. Though the Ag amount is quite little in the hybrid spheres, the electrochemical sensor constructed by the hybrid spheres exhibited fast, stable and well-defined electrocatalytic activity towards H(2)O(2) reduction, which should be the contribution of the combination of Fe(3)O(4) and Ag. The detection limit of H(2)O(2) was also found to be 1.2microM, which was lower than some enzyme-based biosensors.