Regulating the Local Electronic Structure of Copper Single Atoms with Unsaturated B,O-Coordination for Selective ¹O₂ Generation

Abstract

Generating singlet oxygen (1O2) on single atom catalysts (SACs) in peroxymonosulfate (PMS)-based Fenton-like reactions exhibits great potential for selective degradation of contaminants in complex wastewater. Clarifying the structure–activity relationship between the electronic structure of SACs and the 1O2 generation selectivity is crucial for the precise design of efficient Fenton-like catalysts, but it is challenging. Herein, the generation selectivity of 1O2 on Cu SACs with different electronic structures (namely, Cu–O2X, where X = N, S, B, P, and O) is investigated by density functional theory calculations using the adsorption selectivity of terminal oxygen atoms in PMS as an activity descriptor. Significantly, the selectivity of 1O2 generation is affected by the electronic structure of the Cu center in which the electron-depleted Cu-O2B site exhibits a higher selectivity for the adsorption of terminal oxygen atoms. Experimentally, the Cu-O2B moiety exhibits superior catalytic activity for PMS activation, showing nearly 100% selectivity for 1O2 generation and a ciprofloxacin degradation rate of 0.2250 min–1, outperforming those of the other counterparts. The high catalytic activity is attributed to the asymmetric Cu-O2B site accelerating faster electron transfer and O–O bond stretching, lowering the energy barrier of key intermediates toward 1O2 generation. This work provides a broader perspective for regulating the electronic structure of single Cu sites at the atomic level and for the precise design of efficient Fenton-like catalysts.

Regulating the type of nitrogen to improve the performance of Co–N/C with a confinement effect in peroxymonosulfate activation for the effective degradation of organic pollutants

“…Additionally, PMS can be oxidized to SO 5 ˙ − by Co–N/C-2, and SO 5 ˙ − can be further transformed into 1 O 2 . 31 Thus, it is beyond all doubt that the generation pathway of 1 O 2 is in better agreement with facts.…”

Fluorinated Defect-Engineered Acetylenic Polymers with Separated Active Centers for Switching the Photosensitized Activation Pathway of Peroxymonosulfate

“…In situ Raman and FTIR measurements were conducted to analyze the processes of adsorption and catalysis within the PTEB-F 15 /PMS/vis system. The in situ Raman spectra presented in Figure a reveal three distinctive bands centered at 880, 983, and 1062 cm –1 , which are commonly attributed to the adsorbed peroxide species (HSO 5 – ) and the symmetric stretching vibration mode of S–O bonds corresponding to SO 4 2– and HSO 4 – , respectively. ,, The progressive increases in Raman intensity manifested the enhanced binding of reactant PMS with reaction time . The progressive decomposition of PMS could be observed in the change of the ratio of peak intensity at 1062 to 983 cm –1 ( I 1062 / I 983 ) .…”

Were Persulfate-Based Advanced Oxidation Processes Really Understood? Basic Concepts, Cognitive Biases, and Experimental Details

“…In addition to carbonaceous catalysts containing abundant CO groups, catalysts with rich oxygen vacancies, or single-atom catalysts , might also activate PS to mainly produce 1 O 2 . Even almost 100% PMS conversion into 1 O 2 might be observed on single-atom catalysts. ,− 3 S 2 O 8 2 − + 4 H 2 O → 6 SO 4 2 − + O 2 1 + H 2 O 2 + 6 H + HSO 5 − → SO 5 • − + H + + e − SO 5 • − + SO 5 • − → …”

“…Reactive high-valent metal-oxo complexes (RHVMOC, e.g., Fe­(IV) ,,− (usually represent Fe IV O 2+ in Fe 2+ or Fe 3+ systems, and Fe IV O 4 4– or Fe IV O 3 2– in ferrate systems), Fe­(IV)-ligand, , Fe­(V), , Co­(IV), ,, Ni­(IV)-ligand, Cu­(III), , Cu­(III)-ligand, or Mn­(V)-ligand, , in solution; Fe IV O, Fe V O, − Co IV O, ,, Ni &+ O, Ni IV O, Cu III -oxo, ,,, Mn IV -oxo, or Mn V -oxo, on catalysts surface) are also very significant and usually overlooked nonradicals in PS-AOPs (Figure c).…”