The continuous H2O2 detection is shown in Figure . Figure shows the amperometry curve of Fe-N-C SANs during the continuous addition of H2O2 in PBS solution. With the addition of H2O2 solution, the response current increased gradually, which demonstrates the excellent catalytic performance of Fe-N-C SANs. The concentration of H2O2 in the system after adding H2O2 was recorded, and a linear relationship between H2O2 concentration and response current is shown in