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<p>Heterogeneous uptake of <span class="inline-formula">SO₂</span> on mineral dust is a predominant formation pathway of sulfates, whereas the contribution of photo-induced <span class="inline-formula">SO₂</span> oxidation to sulfates on the dust interfaces still remains unclear. Here, we investigated heterogeneous photochemical reactions of <span class="inline-formula">SO₂</span> on five mineral oxides (<span class="inline-formula">SiO₂</span>, kaolinite, <span class="inline-formula">Al₂O₃</span>, <span class="inline-formula">MgO</span>, and <span class="inline-formula">CaO</span>) without photocatalytic activity. Light enhanced the uptake of <span class="inline-formula">SO₂</span>, and its enhancement effects negatively depended on the basicity of mineral oxides. The initial uptake coefficient (<span class="inline-formula"><i>γ</i>_0,BET</span>) and the steady-state uptake coefficient (<span class="inline-formula"><i>γ</i>_s,BET</span>) of <span class="inline-formula">SO₂</span> positively relied on light intensity, relative humidity (RH), and <span class="inline-formula">O₂</span> content, while they exhibited a negative relationship with the initial <span class="inline-formula">SO₂</span> concentration. Rapid sulfate formation during photo-induced heterogeneous reactions of <span class="inline-formula">SO₂</span> with all mineral oxides was confirmed to be ubiquitous, and <span class="inline-formula">H₂O</span> and <span class="inline-formula">O₂</span> played key roles in the conversion of <span class="inline-formula">SO₂</span> to sulfates. In particular, triplet states of <span class="inline-formula">SO₂</span> (<span class="inline-formula">³SO₂</span>) were suggested to be the trigger for photochemical sulfate formation. Atmospheric implications supported a potential contribution of interfacial <span class="inline-formula">SO₂</span> photochemistry on non-photoactive mineral dust to atmospheric sulfate sources.</p>