Singlet oxygen (¹O₂), which is difficult to generate, plays an important role in chemosynthesis, biomedicine and environment. Molecular oxygen (O₂) is a green oxidant to produce ¹O₂ cost-effectively. However, O₂ activation is difficult due to its spin-forbidden nature. Moreover, the main products of O₂ activation are basically hydrogen peroxide (H₂O₂) and hydroxyl radical (•OH), but rarely ¹O₂. Herein, we innovatively realize the selective generation of ¹O₂ via O₂ activation by a facile molybdenum (Mo)/Cu²⁺ system. In this system, Mo firstly reduces Cu²⁺ in solution to low-valence Cu⁰/Cu⁺ on its surface. Cu⁰/Cu⁺ activates O₂ to generate superoxide radical (O₂^•−). Importantly, O₂^•− can be captured immediately and oxidized to ¹O₂ by surface-bound Mo⁶⁺ rather than reduced to H₂O₂. As a result, the Mo/Cu²⁺ system can selectively produce ¹O₂. Under air and O₂ conditions, the degradation efficiency of ibuprofen by Mo/Cu²⁺ system is 67.2 % and 76.6 %, respectively. The degradation efficiencies of bisphenol A, rhodamine B and furfuryl alcohol are 77.1 %, 87.7 % and 91.1 %, respectively. The dosages of Mo and Cu²⁺ are 0.4 g/L and 3 mM, respectively, and the reaction time is 2 h. Interestingly, the activity of Mo decreased by only 4.2 % after 4 cycles. Therefore, this study provides a green pathway to selectively generate ¹O₂ for advanced oxidation processes.

难以生成的单线态氧( ¹ O _{2 )在化学合成、生物医学和环境中起着重要作用。}分子氧 (O ₂ ) 是一种绿色氧化剂，可以经济高效地生产¹ O _{2 。}然而，O ₂激活由于其自旋禁止的性质是困难的。_{此外，O 2}活化的主要产物基本上是过氧化氢(H ₂ O ₂ )和羟基自由基(•OH)，很少有¹ O ₂。在此，我们创新性地实现了O ₂选择性生成¹ O ₂通过简单的钼 (Mo)/Cu ²⁺系统激活。在该体系中，Mo首先将溶液中的Cu ²⁺还原成其表面的低价Cu ⁰ /Cu ^{+ 。}Cu ⁰ /Cu ⁺活化O ₂产生超氧自由基(O ₂ ^•- )。重要的是，O ₂ ^•-可以被表面结合的Mo ⁶⁺立即捕获并氧化成¹ O ₂而不是还原成H ₂ O ₂。因此，Mo/Cu ²⁺系统可以选择性地产生¹ O ₂. 在空气和O ₂条件下，Mo/Cu ²⁺体系对布洛芬的降解效率分别为67.2 %和76.6 %。双酚A、罗丹明B和糠醇的降解效率分别为77.1%、87.7%和91.1%。^{Mo和Cu 2+}的用量分别为0.4 g/L和3 mM，反应时间为2 h。有趣的是，Mo 的活性在 4 个循环后仅下降了 4.2%。因此，本研究为高级氧化过程选择性生成¹ O ₂提供了一条绿色途径。