Developing nonprecious and effective catalysts for electrochemical oxygen evolution reaction (OER) remains a critical challenge among energy conversion technologies. Herein, we developed a novel oxygen-enriched nickel–iron layered double hydroxide (NiFe-LDH) nanosheets electrocatalyst prepared by water-plasma assisted synthesis. The water-plasma engraved oxygen-enriched NiFe-LDH nanosheets possessed a large petal structure of ∼3 μm lateral size with plentiful pores distributed on each flak with 10 nm thicknesses, and a large BET surface area (151 m2 g–1). Profiting by enriched oxygen atoms and fast charge transfer, the oxygen-enriched NiFe-LDH nanosheets displayed a favorable electrocatalytic performance toward OER with a low Tafel slope of 74 mV dec–1 and an overpotential at 10 mA cm–2 for 310 mV in 1.0 M KOH. Such low overpotential was much smaller than initial NiFe-LDH nanosheets (360 mV), and even superior to commercial Ir/C electrocatalyst (370 mV). Sustainable and highly active full water splitting enabled by oxygen-enriched NiFe-LDH nanosheets could be further driven by solar cell or two alkali batteries.

A stable epoxy‐acrylate composite latex was successfully prepared through emulsion polymerization of modified epoxy acrylic (EPAC) oligomer with acrylate monomer. The EPAC oligomer was obtained using active acrylic acid (AA) to react with epoxy resin. And by regulating the reaction degree of the active hydrogen of AA and epoxide group, there is the acquisition of terminal double bond that gives EPAC reactivity, together with the partial retention of the epoxide group that enables self‐crosslinking during film formation. The structural conformation of the oligomer was ascertained by Fourier transform infrared (FTIR) spectroscopy. The factors influencing the stability of the epoxy‐acrylate composite latex were investigated. The epoxy‐acrylate composite latex was the most stable when methyl acrylic acid was 1.5 wt% and modified EPAC oligomer was 15 wt% of the total monomer weight. The morphology and property of the composite latex films were characterized by scanning electron microscopy, transmission electron microscopy (TEM), and temperature‐modulated differential scanning calorimetry (TOPEM‐DSC). The results confirm that there is successful emulsion copolymerization between modified EPAC oligomer and acrylate monomer. TEM show that the particles of epoxy‐acrylate composite have a core‐shell structure, and there is no free epoxy resin. The FTIR and TOPEM‐DSC results reveal that the copolymer emulsion possesses self‐crosslinking ability. During film formation, self‐crosslinking reaction occurs between epoxide groups with carboxyl groups, giving exothermal phenomena. The thermal stability as well as the corrosion resistance of the films was analyzed. The results show outstanding thermal stability as well as corrosion resistance attributable to the crosslinking reticulation structure. It is envisaged that the epoxy‐acrylate composite latex has great potential in the development of high‐performance aqueous coatings.

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A copper (i) polymer, [cu 2 Mg(pzdc) 2 (H 2 o) 5 •2H 2 o] n (pzdc = 2,3-Pyrazinedicarboxylic acid), was synthesized by solvothermal method. The complex was characterized using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectrophotometry (UV-Vis), and element analysis. X-ray crystal structure analysis reveals that the complex is a two-dimensional coordination polymer. The photophysical and luminescent properties of the complex were investigated. At room temperature, the complex exhibits reversible double strands cyclic voltammogram and displays efficient blue emission with peak maxima at 468 nm. Catalytic liquid phase oxidation of dyes and glyphosate was carried out using the copper (i) polymer as catalyst and H 2 o 2 as oxidant. Degradation efficiencies were evaluated by varying the reaction conditions (i.e. illumination and oxidant). In the degradation reactions, the polymer exhibits high degradation efficiency within a short reaction time under the optimum reaction conditions. Furthermore, the reusability of the catalyst is excellent, showing no activity loss in four repeated cycles. The possible reaction mechanism catalyzed by the polymer was inferred on the basis of the results of electron spin resonance (ESR), electrochemical and ion chromatography analyses (IC). Coordination polymers have received considerable attention because of their unique characteristics in terms of magnetic behaviors, optical activities as well as catalytic and luminescent properties. Polycarboxylate ligands were widely studied owing to their rich coordination modes and desired topologies 1-3. Complexes with phthalic acid, pyromellitic acid 4-8 and heterocyclic polycarboxylic acid 9-13 ligands were characterized and investigated. For example, 2,3-pyrazinedicarboxylic acid ligand was involved in the design and synthesis of a large number of Cu and Cu-Ln complexes with novel structures and properties 14-19. Acting as polyfunctional ligand in metal complexes, pyrazine-2,3-dicarboxylate ligand coordinated with transition metal ions using its four carboxylate oxygen atoms and two nitrogen atoms. However, from the structures of the metal complexes, the N and O atoms are not fully utilized in coordination, employing only half or even less for the formation of the complexes. Nonetheless, with the change of reaction condition this traditional ligand could form new types of polymers. Herein, we report the synthesis of a novel Cu-based polymer using simple 2,3-pyrazinedicarboxylic acid as ligand. Based on the polymer structure, it is deduced that five out of the six carboxylate atoms participate in the coordination. Cu-based complexes have attracted much attention because of their luminescent and emission properties, and are widely used in various fields. It is known that their properties are governed by not only the ligand structures but also the steric effect imposed by the ligands 20-23. Generally, Cu (I) complexes with luminescent property can be divided into acetylide clusters, cuprous hali...

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