Heterogeneous La-induced high-spin CoO3 single atom for accelerated Co(IV)=O generation: Boosting ether-PFASs cleavage

A novel spin-state engineering strategy was developed via La doping to break the “oxo wall” and boost high-valent Co(IV)=O generation for efficient per- and polyfluoroalkyl substances (PFASs) degradation. This was achieved by constructing unsaturated CoO 3 single atoms anchored on La-doped MCM-48 (CoLa@MCM-48) via one-pot synthesis, which enabled synergistic activation of peroxymonosulfate and ozone. The optimized catalyst achieved 99.5 % degradation of PFASs substitute sodium p-perfluorous nonenoxybenzene sulfonate (OBS) in 30 min, while maintaining robust performance across diverse water matrices. The incorporation of La induces asymmetric lattice strain through its large ionic radius and spin-orbit coupling, transforming the Co coordination geometry from conventional octahedral symmetry to an unsaturated trigonal planar CoO 3 configuration with a high-spin state, thereby enhancing the 88.8 % generation of Co(IV)=O. This work establishes heteroatom-mediated spin-state engineering for designing high-performance non-radical catalysts to remediate recalcitrant pollutants.