Effect of Fullerene C60 on Sulfate Formation during Gas-Phase Oxidation of SO2 by H2O2

• • Presence of C60 significantly increased sulfate formation during H2O2 gas-phase oxidation of SO2, with higher C60 amounts leading to greater sulfate yields, indicating a direct catalytic role. • • Elevated H2O2 concentrations and UV irradiation enhanced the promoting effect of C60 on sulfate formation, suggesting that oxidant availability and photochemical conditions are critical for maximizing sulfate production. • • XPS analysis revealed electron transfer on the C60 surface, converting adsorbed S(IV) to S(VI), confirming that C60 directly participates in the oxidation process. • • Free radical trapping experiments and model calculations confirmed that C60 promotes the generation of hydroxyl radicals (·OH) and superoxide radicals (·O2−), which are key oxidants driving SO2 oxidation to sulfate.