To further exam the stability of SnOx-Pt/C catalyst during the reverse-current decay process, we conducted ADT up to 1.2 V on RDE. The traditional stability test method is a CV scan test between 0.6 ~ 1.0 V. Here, the CV test range is further increased to 1.2 V, and the oxidation conditions are more stringent (Figure ). The cyclic voltammetry scan is 40,000 cycles, which places high requirements on the catalyst. Compared with the traditional test range, the harsh experimental conditions (0.6 ~ 1.2 V) can better reflect the stability differences of the catalysts. Surprisingly, the SnOx-Pt/C catalyst shows strong antioxidant ability during 40,000 ADT cycles from 0.6 to 1.2 V. The ECSA and mass activity of SnOx-Pt/C catalyst declines 19% and 11%, respectively (Figure ). In contrast, the ECSA and mass activity of Pt/C catalysts reduces by at least 45% and 60%, respectively (Figure ).