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[Display omitted] • The catalysts contain multi-active sites. • The micro twinning structure promotes catalytic activity towards different reactions. • The synergic effect exists and leads to the deviation from the Scaling Effect. The twinning structure could lead to unexpected effects on electrocatalytic performance; however, research on relevant mechanisms is still rare and there is still a lack of an effective and convenient strategy to introduce twinning structures into nanoparticles. In this work, inspired by the in-situ fcc-hcp phase transition in metals and benefiting from the features of Prussian blue analogues (PBAs), N-doped carbon cages-coated CoNi nanoparticles, which contain multi-active sites including alloyed nanoparticles, micro twinning structures and single atom sites could be effectively fabricated by pyrolyzing of CoNi-based PBAs. The catalyst exhibits an obvious enhancement in oxygen evolution/reduction reaction and hydrogen evolution reaction under alkaline conditions. Theoretical calculations verify that the micro-twinning structures originating from the fcc-hcp phase transition promote electrocatalytic activities significantly due to the optimized adsorption energy towards different intermediates. Moreover, the synergic effect between the multi-active sites may further optimize the electronic structures and lead to the deviation from the Scaling Effect. The water-splitting device and Zinc-Air battery are also assembled based on this micro- twinning electrocatalyst, which yields a maximum power density of 95 mW cm−2 and a low voltage of 1.76 V to reach 10 mA cm−2 current density, respectively. In all, this work contributes a simple and universal strategy to introduce both the multi-active sites and the twinning structure into transition metal-based catalysts, which improves the multi-catalytic activity towards different reactions significantly. [ABSTRACT FROM AUTHOR]

A quickly kinetics for de-solvation of hydrate zinc ions benefits from the interaction between electron-donating group and water sheath of hydrated ions. Rich-cyano SEI (rc-SEI) for Zn anode was prepared by coating polyacrylonitrile (PAN) on zinc foil, which realizes low de-solvation activation energy (Ea) of hydrated ions (41.9 kJ mol−1 for rc-SEI@Zn and 63.7 kJ mol−1 for bare Zn). [Display omitted] • Cyano as electron-donating group can interact with sheath of hydrated ions. • Rich-cyano SEI (rc-SEI) reduces de-solvation activation energy of hydrated ions. • Rc-SEI contributes to dendrite-free deposition and high CE of zinc anode. • Rc-SEI improves the cycling performance of a full battery with lean zinc anodes. Aqueous zinc ion batteries (AZIBs) subject to severe sluggish electrodeposition process due to burdensome de-solvation of hydrate zinc ion (Zn(H 2 O) 6 2+→Zn2+) which leads to high overpotential, low utilization of zinc and high interface impedance. Here, an artificial solid electrolyte interphase (SEI) with rich electron-donating functional group (cyano group) is proposed for zinc anode to achieve favorable de-solvation process and deliver stable rechargeable AZIBs. The rich-cyano SEI (rc-SEI) can improve the de-solvation kinetics by formation interaction force between cyano group and water sheath of hydrated ions. The de-solvation activation energy (E a) of hydrated ions for rc-SEI@Zn is only 41.9 kJ mol−1, much lower than that of the bare Zn (63.7 kJ mol−1). The rc-SEI@Zn electrode realizes an enhanced CE of over 99.65 % within 550 cycles in Zn||Cu battery, a low polarization of less than 50 mV and ultra-long cycle life of over 1000 h in Zn||Zn battery. Moreover, Zn||MnO 2 full cell with rc-SEI@Zn anode shows 78.9% capacity retention after 690 cycles at 2C (218.2 mAh g−1 at 1st cycle and 172.1 mAh g−1 at 690th cycle). [ABSTRACT FROM AUTHOR]

• A photothermal method was developed for PDS activation to degrade micropollutants. • 95% of SMX was removed in 3 h, which was faster than that of light activated PDS. • PDS decomposition at high temperature was the main mechanism for the PDS activation. • ·OH and SO 4 ·- were the main species for pollutant degradation during this process. • The method shows a great capacity to degrade micropollutants for water purification. Persulfate activation is a promising advanced oxidation processes to remove micropollutants for the water purification. Persulfate could be activated by heat efficiently, but the continuous energy input limited its application. In this study, a novel photothermal method was developed to activate peroxydisulfate (PDS) to degrade sulfamethoxazole, a widely detected antibiotic in aqueous environments, for water purification. Using the carbon black as the photothermal conversion agent, both heating rate and equilibrium temperature of the solution were enhanced under the simulated sunlight, which was beneficial for PDS activation. By using the developed photothermally-activated PDS method, about 95% of sulfamethoxazole in the aqueous solution could be removed within 180 min, which was 3.28 times faster than that using the individual PDS activated by solar irradiation. Quenching experiment and the electron paramagnetic resonance proved that · OH and SO 4 ·- were the main species for pollutant degradation, and PDS decomposition at high temperature was the main mechanism for the PDS activation by photothermal method. In addition, this photothermally-activated PDS method also showed a great capacity for degrading SMX in the actual water. This work provides a novel and low cost persulfate activation technology for the contaminant removal from the aqueous solution, which shows a great application potential for water purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Based on a dual-confinement regulation, ternary metal-oxide activity sites derived from Co-MOFwere developed. • By chemical confinement, diverse sites were introduced; Then by spatial confinement , Cu x -O-Ni y -O-Co 3-x-y was obtained. • The Cu x -O-Ni y -O-Co 3-x-y modified glassy carbon electrode showed enhanced electrocatalytic activity for glucose oxidation. Based on a dual-confinement strategy on a cobalt-metal-organic framework (Co-MOF), a series of trimetallic-oxide catalysts of Cu x -O-Ni y -O-Co 3-x-y (x/y = 1/1, 1/3, 1/5 and 1/7) were developed for glucose oxidation. By chemical confinement regulation of ion exchange, diverse metal catalytic sites of Cu2+ and Ni2+ were introduced into Co-MOF, respectively; Then by spatial confinement synthesis of pyrolysis, trimetallic MOF of Cu x Ni y Co 3-x-y -MOF was transformed into trimetallic-oxide of Cu x -O-Ni y -O-Co 3-x-y , which maintained the regular morphology and highly ordered lattice structure of Co-MOF. The Cu x -O-Ni y -O-Co 3-x-y composite modified glassy carbon electrode (Cu x -O-Ni y -O-Co 3-x-y /GCE) exhibited enhanced electrocatalytic activity towards glucose oxidation when compared with Co-MOF/GCE, bimetallic MOFs of CuCo-MOF/GCE and NiCo-MOF/GCE, trimetallic MOF of Cu x Ni y Co 3-x-y -MOF/GCE, as well as monometallic oxide Co 3 O 4 /GCE and bimetallic oxides of CuCo 2 O 4 /GCE and NiCo 2 O 4 /GCE, which was mainly due to the synergistic catalysis of electrocatalytically active Co-O-Cu-O-Ni bridges. With Cu2+/Ni2+ molar ratio of 1/3, Cu x -O-Ni y -O-Co 3-x-y /GCE (x/y = 1/3) displayed excellent sensing behaviours on glucose detection. This work not only designed well-performed electrocatalysts for enhancing catalytic activity towards glucose oxidation, but also provided a new perspective to realize the controlled preparation of high-performance electrocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • A strategy to enhanced performance by adding hybrid semiconductive nanofillers. • Achieve U e of 7.2 J/cm3 with high η of 83% at low field (300 MV/m). • Investigate the underlying mechanism of high energy storage performance. Polymer-based nanocomposites with hybrid fillers are expected to possess high energy storage density taking advantage of different morphologies and electric properties of the nanofillers. In this article, hybrid semi-conductive nanofillers with MoS 2 two-dimensional (2-D) nanosheets and ZnO zero-dimensional (0-D) nanoparticles in different ratios were fabricated by the wet chemical route and ultrasonic mixing. The ZnO nanoparticles have a good distribution on MoS 2 nanosheets confirmed by TEM, XRD, and XPS results. The P(VDF-CTFE-DB)/ZnO@MoS 2 composites with different weight percent of fillers were prepared by solution cast, and the influence of hybrid fillers on polymer matrix was systematically investigated. P(VDF-CTFE-DB) with hybrid filler exhibits optimized discharged energy density of 7.2 J/cm3 and efficiency of 83% at 300 MV/m, both of which are higher than those reported in polymer nanocomposites at the same electric field. Moreover, the distribution of polarization and electric field of the distribution of 2D fillers in four different models for composite P(VDF-CE-DB)/ZnO@MoS 2 with 2 mol% of fillers were investigated by the finite element simulation analysis (COMSOL). In addition, the nanocomposite also possesses high power density and excellent fatigue reliability, demonstrating it can be a good candidate for energy storage device that requires high energy density at a low electric field for safer working conditions. [ABSTRACT FROM AUTHOR]