Superior Singlet Oxygen Electrosynthesis via Neighboring Dual Molecular Oxygen Coactivation for Selective Tetracycline Detoxification

Oxygen (O2) electroreduction offers a green approach for singlet oxygen (1O2) synthesis in wastewater contaminants detoxification. However, traditional single O2 activation on single‐metal catalytic sites seriously suffers from the kinetically‐unfavorable desorption of adsorbed superoxide species (•O2−*/•OOH*). Here, we demonstrate a novel dual O2 coactivation pathway on shortened Fe1−OV−Ti sites for superior 1O2 electrosynthesis through a rapid disproportionate process between surface‐confined •O2−*/•OOH*. Theoretical calculations combined with in‐situ electrochemical spectroscopies demonstrated that the shortened distance between Fe single atom and adjacent unsaturated Ti atom facilitates the direct recombination of surface‐confined Fe−•OOH and Ti−•OO− to yield 1O2, bypassing the formidable •O2−*/•OOH* desorption process. Impressively, Fe1−OV−Ti could realize an excellent 1O2 electrosynthesis rate of 54.5 μmol L−1 min−1 with an outstanding 1O2 selectivity of 97.6% under neutral condition, surpassing that of Fe1−O−Ti (27.1 μmol L−1 min−1, 91.7%). Using tetracycline (TC) as a model pollutant, the resulting Fe1−OV−Ti electrode achieved nearly 100% degradation in 120 min at ‐0.6 V, meanwhile preventing the generation of toxic intermediates. This study provides a new 1O2 electrosynthesis strategy by controlling the distance of adjacent catalytic sites for the coactivation of dual molecular oxygen.