Deciphering highly resistant characteristics to different pHs of oxygen vacancy-rich Fe2Co1-LDH/PS system for bisphenol A degradation

Rational Construction of a N, F Co‐doped Mesoporous Cobalt Phosphate with Rich‐Oxygen Vacancies for Oxygen Evolution Reaction and Supercapacitors

“…Therefore, according to previously reported studies, this amorphous structure associated with defect-rich could decrease the energy barrier and provide more active sites for boosting OER performance. [41][42][43][44][45][46][47] We further studied the surface electronic structure and valence state of the as-prepared material before and after calcination by X-ray photoelectronic spectra (XPS, Figure 4), which further confirms the existence of N, O, F, P, and Co elements in the pristine NCoHPOF and NCoHPOF-450, consistent with the above results such as TEM and EDX.…”

“…On the other hand, in the F 1s high-resolution spectrum, the binding energy of the NCoHPOF catalyst splits into two peaks at 684.3 and 686.8 eV, corresponding to the CoÀ FÀ Co and FÀ Co bonds. [31][32][33] While, after calcination, for NCoHPOF-450, it has only one weaker peak at 686.3 eV, which can be ascribed to the release of HF in the pyrolysis process, in line with TGA result; meanwhile, three peaks at 531.3, 532.4 and 533.9 eV can be responded to the lattice oxygen, vacancy oxygen and surface adsorbed hydroxy species, [5,[45][46][47] respectively, it should be noted that the peak of oxygen vacancy is different from many reported results, which should be due to the chemical shift and binding energy changes of the oxygen vacancies in metal phosphate system with different environment. [45][46][47] In addition, the P 2p spectrum of NCoHPOF and NCoHPOF-450 can be divided into two peaks at P 2p3/2 (133.4 eV) and P 2p1/2 (134.2 eV), attributed to PÀ O bond, especially, the P 2p spectrum of NCoHPOF-450 shifted 0.2 eV toward higher binding energy compared with that of NCoHPOF, which might be ascribed to the formation of oxygen vacancies and pyrophosphate.…”

“…[31][32][33][34][35][36] Notably, compared with NCoHPOF, the ratio of Co 2 + /Co 3 + in NCoHPOF-450 increases from 1.68 to 1.76, which should be ascribed to the appearance of oxygen vacancies. [5,[45][46][47] Besides, from N 1s spectrum, a characteristic peak at 401.7 eV is corresponding to the NÀ H bond of NH 4 + cations in NCoHPOF, after calcination, while, there are two fitted peaks at 401.9 and 399.9 eV, attributed to the formation of the CoÀ N bond. On the other hand, in the F 1s high-resolution spectrum, the binding energy of the NCoHPOF catalyst splits into two peaks at 684.3 and 686.8 eV, corresponding to the CoÀ FÀ Co and FÀ Co bonds.…”

A Review Study on Sulfate-Radical-Based Advanced Oxidation Processes for Domestic/Industrial Wastewater Treatment: Degradation, Efficiency, and Mechanism

“…The category of the intermediates is closely related to the degradation pathway and reaction conditions. Wu et al (2020) found that the molecular weights of the oxidative intermediates of BPA within the Fe 2 Co 1 -LDH/PS system decreased significantly when the reaction time increased from 10 to 30 to 60 min. The addition of different catalytic components also significantly affects the intermediate products; for instance, the intermediates of BPA in the Fe 3 O 4 /coal fly ash/PS system were different from those obtained from the CoS@GN-60/PMS system (Zhu et al, 2019).…”

“…However, excessive sulfite will scavenge SO − 4 • and inhibit substrate oxidation. The concentration and behavior of SO 4 − • can be analyzed via radical trapping experiments and electron paramagnetic resonance detection (Liu Y. et al, 2019;Wu et al, 2020). Further oxidation of H 2 O or OH − by SO 4 − leads to the generation of OH• (Equations 39-40), which would be another key reason for pollutant oxidation.…”