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[Display omitted] • The ultrathin Ni-phyllosilicate was successfully synthesized by ball milling method. • H 2 O 2 played a crucial role of pore-forming reagent to create defects in Ni-phyllosilicate. • Nickel acetylacetonate was the optimal nickel salt precursor to form Ni-phyllosilicate. • Metal utilization rate was significantly improved owing to the ultrathin defect-rich structure. • The optimum catalyst exhibited enhanced low-temperature activity for CO 2 methanation. To address the problems of low metal utilization rate and poor low-temperature activity of the nickel phyllosilicate catalysts for CO 2 methanation, this work prepared ultrathin defect-rich Ni-phyllosilicate through ball milling method in the presence of H 2 O 2 modifier, which simultaneously created active sites with more quantity and higher quality. The instantaneous temperature and high pressure derived from the collision and friction of grinding balls provided driving force for the Ni-phyllosilicate synthesis, and the shear force destroyed the interlayer forces to construct the ultrathin layers. H 2 O 2 molecule could insert the layers and dissociate to O 2 bubbles, whose cavitation effect created holes and defects in the nickel phyllosilicate nanosheets and SiO 2 spheres. H 2 O 2 amount was crucial for the defect construction and the optimum Ni-AA-1H catalyst possessed the ultrathin nanosheet of 0.68 nm and high Ni dispersion of 15.6 %, whose TOF CO2 reached 3.76 × 10−2 s−1 at 160 °C. The in-situ DRIFTS results confirmed the enhanced low-temperature activity and the HCOO− reaction pathway over Ni-AA-1H for CO 2 methanation. Nickel precursor effect was also investigated, and nickel acetylacetonate was determined as the optimal one compared with nickel acetate and nickel chloride, owing to the high steric effect of CH 3 COCHCOCH 3 − group and strong basicity environment during ball milling process. [ABSTRACT FROM AUTHOR]

[Display omitted] • An anaerobic–aerobic-coupled upflow bioelectrochemical reactor was constructed. • Intermittent electrical stimulation mode promoted phenolics degradation. • Aerobic cathodic chamber showed high contribution to the phenolics removal. • Specific microbes were enriched in the cathodic and anodic chambers of the system. Phenolics were widespread in the effluents of coal gasification plants and oil refineries processes, while the impact of electrical stimulation on phenolics degradation in the combined biological processes remained unclear. Here, a novel anaerobic–aerobic–coupled upflow bioelectrochemical reactor (AO-UBER) was used to treat phenol-containing synthetic wastewater and simulated phenolic wastewater. The AO-UBER could treat phenolic compounds effectively via electrical stimulation. Phenol and total phenol removal efficiencies in the intermittently electrically stimulated system with a hydraulic retention time of 6 h were about 22.6% and 31.1%, respectively, higher than that in the biological system not exposed to voltage. The contribution of the aerobic cathodic chamber to the removal of phenolic compounds was higher than that of the anaerobic anodic chamber under the intermittent voltage application mode. High-throughput sequencing analysis indicated that electrical stimulation selectively enriched Acinetobacter , Cloacibacterium , Acidovorax, and Zoogloea in the phenol-containing synthetic wastewater treatment process, and Rhodococcus , Achromobacter , Chryseobacterium, and PSB-M-3 in the simulated phenolic wastewater treatment process. These results demonstrate that the AO-UBER under intermittent voltage application mode holds good potential for efficient phenolic wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • An anaerobic–aerobic-coupled upflow bioelectrochemical reactor was constructed. • Intermittent electrical stimulation mode promoted phenolics degradation. • Aerobic cathodic chamber showed high contribution to the phenolics removal. • Specific microbes were enriched in the cathodic and anodic chambers of the system. Phenolics were widespread in the effluents of coal gasification plants and oil refineries processes, while the impact of electrical stimulation on phenolics degradation in the combined biological processes remained unclear. Here, a novel anaerobic–aerobic–coupled upflow bioelectrochemical reactor (AO-UBER) was used to treat phenol-containing synthetic wastewater and simulated phenolic wastewater. The AO-UBER could treat phenolic compounds effectively via electrical stimulation. Phenol and total phenol removal efficiencies in the intermittently electrically stimulated system with a hydraulic retention time of 6 h were about 22.6% and 31.1%, respectively, higher than that in the biological system not exposed to voltage. The contribution of the aerobic cathodic chamber to the removal of phenolic compounds was higher than that of the anaerobic anodic chamber under the intermittent voltage application mode. High-throughput sequencing analysis indicated that electrical stimulation selectively enriched Acinetobacter , Cloacibacterium , Acidovorax, and Zoogloea in the phenol-containing synthetic wastewater treatment process, and Rhodococcus , Achromobacter , Chryseobacterium, and PSB-M-3 in the simulated phenolic wastewater treatment process. These results demonstrate that the AO-UBER under intermittent voltage application mode holds good potential for efficient phenolic wastewater treatment. [ABSTRACT FROM AUTHOR]

• Strong coupling was established between NiCo-DH and OAC by oxidation modification. • NiCo-DH@OAC exhibited excellent electrochemical performance for synergistic effects. • ASCs were demonstrated effective in solar panel integrated supercapacitors. NiCo double hydroxide (NiCo-DH) and oxidized activated carbon (OAC) were used to synthesize a three-dimensional (3D) NiCo-DH@OAC via hydrothermal method. OAC acts as the support for in-situ growth of NiCo-DH nanowires, and oxygen-containing groups on the surface of OAC are crucial for the uniform loading of NiCo-DH and keeping structural stability of the composites. Due to the synergistic effect between NiCo-DH and OAC, NiCo-DH@OAC presents an excellent specific capacitance (1990 F g−1 at 1 A g−1). The asymmetric supercapacitor (ASC) is assembled with NiCo-DH@OAC as the positive electrode and OAC as the negative electrode, and exhibits a superior energy density (46.5 Wh kg−1 at 800 W kg−1) and a cycling stability (90.7% after 10,000 cycles). Furthermore, ASC has been demonstrated effective in solar panel integrated supercapacitors. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel sorbent was prepared for simultaneous removal of H 2 S and Hg0 in natural gas. • H 2 S and Hg0 capacities of 1Cu1Zn/SBA-15 were 296.78 mg·g−1 and 12.75 mg·g−1 at 10% breakthrough. • The 1Cu1Zn/SBA-15 sorbent exhibited excellent the regeneration performance over 5 cycles. • the S n 2− formed by chemisorption of H 2 S are the active sites for Hg0 capture. Inspired by the fact that H 2 S can easily decompose on some metal oxides to form sulfur species and the resulting products are usually used as Hg0 removal active sites, a novel Cu-Zn mixed oxide supported SBA-15 zeolite was controllably synthesized for simultaneous removal of Hg0 and H 2 S. The Cu-Zn nanoparticles with a particle size range of 4.4–5.0 nm were successfully confined and uniformly dispersed in the two-dimensional mesopores of SBA-15. The obtained 1Cu1Zn/SBA-15 adsorbent presented an outstanding H 2 S and Hg0 removal efficiencies at 30 °C and 30,000 h−1, and the H 2 S and Hg0 capture capacities reached to 296.78 mg·g−1 and 12.75 mg·g−1 at a 10% breakthrough. In addition, the spent adsorbent could be regenerated in a 5% O 2 and 95% N 2 atmosphere at 600 °C without obvious degradation of adsorption capacities over five cycles. We considered that the doping effects of Cu-Zn oxides were beneficial for its excellent H 2 S and Hg0 removal performance at low temperatures, and the nano-confinement effect of SBA-15 was conducive to prevent the oxides nanoparticles from agglomeration in the regeneration process, thus achieving the outstanding regeneration performance. Furthermore, the polysulfide polymer formed by chemisorption of H 2 S on the Cu-Zn oxides surface was confirmed to be the Hg0 active sites, which could react with gaseous mercury to form HgS. This work provided an effective way for simultaneous removal of H 2 S and Hg0 in natural gas by confining nano-sized active metal oxides into the mesopores of zeolites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Applying electric field suppressed membrane fouling rate of AnMBR. • Applying electric field decreased the deposition of organic foulants on membrane. • Contribution of electrophoresis to membrane fouling suppression was quantified. • Applying electric field improved mixed liquor filterability of AnMBR. • Mechanism of mixed liquor filterability improvement was analyzed. Anaerobic membrane bioreactor (AnMBR) is a promising technology for wastewater treatment. However, membrane fouling as an inevitable challenge restricts its application. Recently novel membrane fouling control technology by applying electric field in AnMBR showed its economics and effectiveness. Nevertheless, the mechanism of fouling suppression is still unclear, limiting the development of this technology. In this study, electro-AnMBR was constructed. Long-term running showed that applying electric field of 0.5 V suppressed the membrane fouling evolution rate by nearly 23% and reduced the organic foulants on membrane by nearly 10%. To clarify the mechanism of fouling suppression, the contribution of electrophoresis to membrane fouling suppression was quantified by theoretical calculation for the first time. Results showed that electrophoresis was approximately equivalent to backwash with a flux of 0.56 L/(m2·h). Besides, impact of electric field on mixed liquor filterability of AnMBR was first investigated by dead-end filtration. Results presented that electric field reduced the filtration resistance of mixed liquor by nearly 77%. Then mixed liquor properties analysis, electrochemical oxidation simulation tests and metagenomic analysis revealed that electric field might improve mixed liquor filterability by bioelectrochemical oxidation. Finally, novel mechanism of electric field suppressed membrane fouling was elucidated, including electrophoresis to drive off the foulants and mixed liquor filterability improvement. This study might contribute to better understanding for membrane fouling control by applying electric field in AnMBR, and was meaningful for technical development. [ABSTRACT FROM AUTHOR]