<p>Developing efficient catalysts for low-temperature O₂ activation is critical for energy-efficient heterogeneous catalysis, yet designing highly active and accessible active sites remains a formidable challenge. Here, we construct a new type of zero-valent platinum single atoms (Pt⁰ SAs) on two-dimensional Co₃O₄ through a feasible low-temperature reduction strategy. By eliminating oxygen coordination, we induce strong Pt−Co electronic interactions and optimize the Pt 5 <i>d</i> band center, promoting electron donation that strengthens O₂ activation. In contrast, conventional high-valent Pt⁴⁺ SAs, which rely on oxygen vacancy formation, exhibits weaker O₂ activation. Consequently, Pt⁰ SAs achieves a 9.3-fold higher turnover frequency in toluene oxidation than does the Pt⁴⁺ SAs at 140 °C (the temperature at which a toluene conversion efficiency of 90% is achieved). This work highlights electronic modulation in optimizing O₂ activation and affords a strategy for designing highly efficient zero-valent single atom catalysts.</p>