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[Display omitted] • The metal–oxygen-carbon bonds boosted interfacial electron transfer. • Ozone utilization efficiency was higher (ΔTOC/ΔO 3 = 1.23–0.68) in Fe 2 Co@CS/EP compared with EP. • Catalytic ozonation played the dominant role in · OH, · O 2 − and 1O 2 generation. • Fe 2 Co@CS/EP presented an enormous potential in wastewater treatment. We fabricated a novel Fe-Co bimetal encapsulated inside carbon aerogel sphere (Fe 2 Co@CS) to improve the electro-peroxone (EP) process. The degradation and mineralization of p -nitrophenol (p -NP) were 100% (15 min) with rate constant of 0.314 min−1 and 83.8% (60 min) in Fe 2 Co@CS/EP, respectively. Fe 2 Co@CS was composed of defective graphite carbon and Fe 2 Co alloy. The presence of metal–oxygen-carbon (M-O-C, M Fe/Co) bonds promoted interface electron transfer from carbon layer towards Fe 2 Co alloy, which was advantageous to the reduction of ≡Fe3+/≡Co3+. Moreover, the Fe-Co synergistic effect also accelerated the interfacial catalytic reaction for activating O 3 and H 2 O 2. The quenching experiment and EPR test indicated that · OH, · O 2 - and 1O 2 were main reactive oxygen species (ROSs). DFT calculations showed that O 3 had lower adsorption energy on Fe 2 Co@CS than H 2 O 2 , manifesting that catalytic ozonation played the key role in ROSs generation. In addition, ozone utilization efficiency in Fe 2 Co@CS/EP (ΔTOC/ΔO 3 = 1.23–0.68) revealed 66-36% increase relative to those of EP (0.74–0.5). Fe 2 Co@CS was an efficient catalyst over a wide pH range (3–11) with permissible iron and cobalt releases. The Fe 2 Co@CS/EP process exhibited high-performance for degrading different pollutants under high salinity condition with coexistence of Cl−, NO 3 − and SO 4 2−. For treating real coal wastewater, the TOC removal was 52.7% at 4 h with low EEC (0.038 kWh (g TOC)−1). This study provided an efficient method for the development of EP in wastewater treatment. [ABSTRACT FROM AUTHOR]

Recognizing the high energy consumption for in-situ generation of H 2 O 2 and low mass transfer of O 3 in electro-peroxone (EP), Fe0 embedded in carbon sphere (Fe0@CS) was synthesized to fulfill the efficient treatment of various pollutants. At optimal condition, the degradation and mineralization of 100 mg/L phenol were 100% with k (0.20 min−1) at 15 min and 72.1% at 60 min with iron dissolution (1.61 mg/L) and low energy consumption (0.067 kWh (g TOC)−1). The utilization efficiency of O 3 and H 2 O 2 increased by 1.9 – 11.5% and 16.8 – 27.1%, respectively. Fe2+ originated from the faster H 2 O 2 corrosion, initiated heterogeneous Fenton-like and catalytic ozonation reaction. The quenching and electron paramagnetic resonance experiments manifested the existence and mutual transformation of •OH, •O 2 - and 1O 2 , among which •OH was dominant. Fe0@CS/EP realized the simultaneous catalysis of O 3 and H 2 O 2 over wide pH 3 – 10, which had broad prospects for wastewater purification. [Display omitted] • Fe0 embeded in carbon sphere was synthesized for electro-peroxone (EP). • Fe0@CS facilitated pollulant removal with low Fe leaching and energy consumption. • Fe0@CS/EP realized the simultaneous catalysis of O 3 and H 2 O 2 over wide pH 3–10. • H 2 O 2 corrosion to Fe0 played the key role in Fe0@CS/EP. • •OH, •O2- and 1O 2 were involved in Fe0@CS/EP, while •OH was dominant. [ABSTRACT FROM AUTHOR]

• B,Co-TNT anode was first used for EA-PS system for CBZ degradation. • A higher CBZ degradation was achieved in flow-through mode ascribed to the higher PS decomposition for OH production. • CBZ degradation by EA-PS in flow-through system were the comprehensive effect of OH, SO 4 − and 1O 2. • EA-PS in flow-through system was an effective method for contaminants degradation. Degradation of carbamazepine (CBZ) was first conducted by electrochemical activation of persulfate (PS) in flow-through system using boron and cobalt co-doped TiO 2 nanotubes (B, Co-TNT) as the anode and carbon felt (CF) as the cathode, achieving a higher removal efficiency than that in beaker mode ascribed to the higher PS decomposition for OH production. Different operating parameters including applied current, initial pH, PS concentration and flow rate were explored, supporting that high current, acidic condition, lofty PS concentration and flow rate were beneficial for the removal of CBZ. The mechanisms of CBZ degradation by electrochemical activation of persulfate in flow-through system were the comprehensive effect of OH, SO 4 − and 1O 2 , and the possible CBZ degradation pathway was proposed. In summary, B, Co-TNT anode coupled with CF cathode in flow-through system by electrochemical activation of persulfate was an effective method for contaminants degradation. [ABSTRACT FROM AUTHOR]

A flow-through system was constructed for 2,4-dichlorophenoxyacetic acid (2,4-D) degradation for the first time using efficient boron and cobalt co-doped TiO 2 nanotubes (B, Co-TNT) as the anode and carbon black doped carbon felt (CB-CF) that had a high H 2 O 2 yield as the cathode. Compared with dimensionally stable anode (DSA), whether in anodic oxidation (AO) or AO-electro-Fenton (EF) system, 2,4-D degradation in B, Co-TNT anode system was more efficient accompanying with a lower energy consumption (Ec). Different operating parameters including applied current density, initial pH and flow rate were explored, supporting that the optimal Fe2+ dosage was 0.5 mM while decreasing the initial pH and increasing the current intensity and flow rate were beneficial to 2,4-D removal. In this AO-EF system, the involved mechanisms for 2,4-D degradation were anodization and Fenton oxidation, possessing the comprehensive effect of •OH and SO 4 •- with their contribution of 92.7% and 4.8%, respectively. This flow-through AO-EF system performed a stable performance, and an efficient degradation performance with low Ec (5.8–29.5 kWh (kg TOC)−1) was obtained for different kinds of contaminants (methylene blue, phenol, p -nitrophenol and sulfamethazine). Therefore, B, Co-TNT anode coupled with CB-CF cathode in flow-through system was effective for contaminants degradation. [Display omitted] • B,Co-TNT anode was first used for flow-through electro-Fenton (EF) for 2,4-D degradation. • More efficient performance and lower Ec were observed on B,Co-TNT compraed with DSA. • The contribution of.•OH and SO 4 •- for 2,4-D degradation was 92.7% and 4.8% respectively. • Flow-through EF on B,Co-TNT anode was cost-effective for contaminants degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • QFASA was used for the first time to identify sources of indoor organic pollutants. • OPFR concentrations and lipid content in house dust were significantly related. • Clothing was the predominant contributing vector introducing indoor OPFRs. • QFASA can accurately predict most of OPFR concentrations in clothing. Indoor dust has been used as a proxy for estimating human indoor pollutant exposure risks, yet source identification remains challenging. This study tentatively investigated whether quantitative fatty acid signature analysis (QFASA) of dust, could be applied to indicate sources and their respective contributions for a major class of indoor organic pollutants organophosphate flame retardants (OPFRs). We observed significant correlations between OPFR concentrations and lipid content (p < 0.05) in house dusts. Using 15 signature fatty acids (FAs) in various indoor sources and the QFASA model, we found that clothing (39.1% in Australia and 36.5% in China) was the predominant contributing vector of dust OPFR followed by cooking oil and pet hair. Among these sources, clothing materials were proposed to be important vectors introducing organic pollutants to the indoor environment. Our QFASA contribution estimation analyses allowed for accurate prediction of most OPFR concentrations in clothing, validating our findings that clothing materials may serve as important carrier for OPFRs in indoor migration. This is the first study attempting to identify sources of organic pollutants using QFASA in an indoor setting and will provide important insight into the transfer of organic pollutants in indoor environment. [ABSTRACT FROM AUTHOR]

• F-Fe-MCM-41 possessed excellent activity in catalytic ozonation of NB. • F planting enhanced the hydrophobicity and Lewis acids of Fe-MCM-41. • The liquid and solid interface reaction mechanism was proposed. • OH scavenging effect of humic acid and carbonate were weakened by F-Fe-MCM-41. Heterogeneous catalytic ozonation had met the bottlenecks when treating low concentration but high toxic pollutants: (i) the low mass transfer efficiency of ozone and pollutants to hydrophilic catalyst; (ii) the negative impact of coexisted water matrixes. Herein, to enhance the mass transfer efficiency of reactants toward hydrophilic Fe-MCM-41 as well as enhance the interfacial reaction, the fluoride planting Fe-MCM-41 (F-Fe-MCM-41) was synthesized and employed as catalyst in catalytic ozonation for nitrobenzene (NB). Both NB and TOC removal were promoted in F-Fe-MCM-41/O 3 with 99.0 % NB removal in 60 min and 88.6 % TOC removal in 120 min, which were superior to the degradation efficiency by O 3 and Fe-MCM-41/O 3. FTIR, EPR, Mössbauer spectra, 29Si NMR, 19F NMR et al verified that the replacement of non-reactive silanols (-Si−OH) of Fe-MCM-41 with Si F groups could enhance its hydrophobicity, Lewis acidity and mass transfer effect. Comparative characterizations, experiments and theoretical calculations verified that interfacial reaction played the major role over liquid phase reaction for NB degradation in F-Fe-MCM-41/O 3. Moreover, the strengthened interfacial reaction also reduced the OH scavenging effect of water matrix, such as humic acid and carbonate. The interfacial adjustment method proposed in this study provided a novel insight into catalyst design and water treatment process. [ABSTRACT FROM AUTHOR]