2026-10-11T23:56:20Z https://www.scidb.cn/oai

10.57760/sciencedb.011bi 2026-09-03T11:09:42Z

2026-09-03 Asymmetric Coordination-Engineered High-Spin Iron Single-Atom Catalysts Facilitating 3d-2p Orbital Hybridization for Superior Persulfate Activation doi:10.57760/sciencedb.011bi en The optimization of spin states and local coordination environments is a powerful strategy for improving catalytic performance in advanced oxidation processes. Here, we present a single-atom iron catalyst embedded in a crystalline carbon nitride framework (Fe-CCN-H) that demonstrates exceptional efficiency in activating persulfate (PDS) to degrade recalcitrant emerging contaminants. Such high activity is due to the strong interactions between the 3d-orbitals of the asymmetric low-coordination Fe and the σ*2p orbitals of PDS. In situ electron paramagnetic resonance (EPR), X-ray absorption spectroscopy (XAS), Raman spectroscopy, and density functional theory (DFT) calculations reveal that Fe 3dyz orbitals interact with σ* orbitals of S=O bonds in PDS to enhance PDS adsorption, while Fe 3dxz orbitals effectively drive PDS conversion to ·SO4−. Concurrently, electron transfer from adsorbed water molecules through the carbon nitride lattice to Fe 3dx2−y2 orbitals generates hydroxyl radicals (·OH), enabling synergistic oxidation by ·SO4− and ·OH. As a result, Fe-CCN-H exhibits superior efficiency and stability, achieving a pseudo-first-order rate constant (k) of 0.05548 min−1 for diclofenac degradation 17.0 and 7.6 times higher than that of CCN-H (0.00326 min−1) and Fe-CCN (0.00729 min−1), respectively. High-spin atomic iron; Thermodynamically favorable d-orbital configuration; Catalytic activation of persulfates; in situ electron paramagnetic resonance; Emerging contaminants li dexuan RESTRICTED dataset Science Data Bank