An insight into metal organic framework derived N-doped graphene for the oxidative degradation of persistent contaminants: formation mechanism and generation of singlet oxygen from peroxymonosulfate

Abstract

The synthesis of carbonaceous materials from a metal organic framework (MIL-100), organic linker and N-precursor was comprehensively investigated, and the structures of the products were characterized. It was found that simple pyrolysis of mixed MIL-100 (Fe)/dicyandiamide (DCDA) could produce nitrogen-doped graphene (N-graphene). The N-graphene showed excellent performances in peroxymonosulfate (PMS) activation, which were superior to those of counterparts of graphene, iron(ii, iii) oxide, manganese(iv) oxide and cobalt(ii, iii) oxide. With PMS activation, N-graphene exhibited efficient catalytic degradation of various organic pollutants such as phenol, 2,4,6-trichlorophenol (TCP), sulfachloropyridazine (SCP) and p-hydroxybenzoic acid (PHBA). Electron paramagnetic resonance (EPR) spectroscopy and radical quenching tests were employed to investigate the PMS activation and organic degradation processes. It was found that singlet oxygen (1O2) was mainly produced during the activation of PMS by N-graphene, and contributed to the catalytic oxidation instead of sulfate and/or hydroxyl radicals. These findings provide new insights into PMS activation by metal-free carbon catalysi

Superior three‐dimensional perovskite catalyst for catalytic oxidation

“…40 Besides that, the decomposition of PMS gives rise to the generation of singlet oxygen. 38,41,42 We also observed that the significant current increase toward LSC electrode with PMS existing in the LSV test Figure 5D), which directly verifies the interaction between PMS and LSC in which electrons were transferred from PMS to LSC. 43 Based on the above discussion, the possible mechanism of PMS activation by LSC hollow fiber catalyst was illustrated in Figure 5E, and the possible reaction steps were described as below:…”

“…•− were captured by radical spin tapping agent of 5,5-dimethyl-1-pyrroline N-oxide (DMPO). 7,38 The observed DMPO-X is denoted as the oxidized DMPO. 39 Moreover, the typical peaks of singlet oxygen in Figure 4C are detected by trapping agent of 2,2,6,6-tetramethyl-4-piperidinol (TMP), indicating that the existence of LSC hollow fiber catalyst contributes to the formation of 1 O 2 .…”

Tailored synthesis of active reduced graphene oxides from waste graphite: Structural defects and pollutant-dependent reactive radicals in aqueous organics decontamination

“…POPs [2][3][4]. Advanced oxidation processes (AOPs) with the generated active radicals become the hotspot due to their fast reaction rates with organics and complete mineralization capability [5][6][7].…”

Strongly Coupled g‐C3N4 Nanosheets‐Co3O4 Quantum Dots as 2D/0D Heterostructure Composite for Peroxymonosulfate Activation

“…Advanced oxidation processes (AOPs) have attracted a wide attention for completely decomposition of organic pollutants by producing radicals . As one of the most popular AOPs, the∙OH generated from H 2 O 2 through the homogeneous/heterogeneous Fenton reaction is highly recognized to degrade various organic compounds; however, disadvantages such as acidic pH condition, relatively low efficiency, and instability of H 2 O 2 remains a problem .…”