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A cost-efficient and stable oxygen evolution electrocatalyst is essential for improving energy storage and conversion efficiencies. Herein, 2D nanosheets with randomly cross-linked CoNi layered double hydroxide （LDH） and small CoO nanocrystals were designed and synthesized via in situ reduction and interface- directed assembly in air. The formation of CoNi LDH/CoO nanosheets was attributed to the strong extrusion of hydrated metal-oxide clusters driven by the interfacial tension. The obtained loose and porous nanosheets exhibited low crystallinity due to the presence of numerous defects. Owing to the orbital hybridization between metal 3d and O 2p orbitals, and electron transfer between metal atoms through Ni-O-Co, a number of Co and Ni atoms in the CoNi LDH present a high ＋3 valency. These unique characteristics result in a high density of oxygen evolution reaction （OER） active sites, improving the affinity between OH- and catalyst, and resulting in a large accessible surface area and permeable channels for ion adsorption and transport. Therefore, the resulting nanosheets exhibited high catalytic activity towards the OER. The CoNi LDH/CoO featured a low onset potential of 1.48 V in alkaline medium, and required an overpotential of only 300 mV at a current density of 10 mA.cm-2, while displaying good stability in accelerated durability tests.

Layered double hydroxides （LDHs） are a materials with extensive applications and class of two-dimensional （2D） layered well-developed synthesizing methods in aqueous media. In this work, we introduce an alcohothermal synthesis method for fabricating NiFe-LDHs with dehydrated galleries. The proposed process involves incomplete hydrolysis of urea for the simultaneous precipitation of metal ions, with the resulting water-deficient ethanol environment leading to the formation of a dehydrated structure. The formation of a gallery-dehydrated layer structure was confirmed by X-ray diffraction （XRD）, as well as by a subsequent rehydration process. The methodology introduced here is also applicable for fabricating Fe-based LDHs （NiFe-LDH and NiCoFe-LDH） nanoarrays, which cannot be produced under the same conditions in aqueous media because of the different precipitation processes involved. The LDH nanoarrays exhibit excellent electrocatalytic performance in the oxygen evolution reaction, as a result of their high intrinsic activity and unique structural features. In summary, this study not only introduces a new method for synthesizing LDH materials, but also provides a new route towards highly active and robust electrodes for electrocatalvsis.

Engineering complex nanocomposites that specifically target the hepatitis B virus （HBV） and overcome the limitations of current therapies such as limited efficacy and serious side effects is very challenging. Here, for the first time, the antiviral effect of engineered plasmonic gold and layered double hydroxide self-assemblies （AuNPs/LDHs） is demonstrated, using HBV as a model virus and hepatoma-derived HepG2.2.215 ceils for viral replication, assembly, and secretion of infectious virions and subviral particles. AuNPs/LDHs were obtained by a simple, cost-effective procedure in which small AuNPs （-3.5 nm） were directly obtained and organized on the surface of larger LDH nanoparticles （-150 nm） by exploiting the capability of MgLDH, ZnLDH, and MgFeLDH to manifest their ＂structural memory＂ in the aqueous solution of Au（O2CCH3）3. The self-assembly approach of AuNPs and LDHs was assessed by transmission electron microscopy （TEM）, X-ray photoelectron spectroscopy （XPS）, powder X-ray diffraction （PXRD）, and UV-Vis analysis （UV-Vis）. All AuNPs/LDHs tested reduced the amount of viral and subviral particles released from treated cells by up to 80% and exhibited good cytocompatibility. AuNPs/MgFeLDH showed the highest antiviral HBV response with more than 90% inhibition of HBV secretion for the whole concentration range. Preliminary studies on the mechanism of HBV inhibition reveals that in the presence of AuNPs/LDHs, HBV particles are sequestered within the treated cells. The antiviral and low cytotoxic plasmonic properties of these Au/LDH nanocomposites indicate that they hold significant potential to be tailored as novel efficient therapeutics for the treatment of hepatitis B.

Fluorescence resonance energy transfer （FRET） systems have broad applications in visual detection, intelligent materials, and biological imaging, all of which favor the transmission of light through multiple dimensions and in diverse directions. Herein, we have demonstrated multi-dimensional （0D and 2D） FRET within a multi-layer ultrathin film （UTF） by employing a layer-by-layer （LBL） assembly technique. The anionic block copolymer micelle poly（tert-butyl acrylate- co-ethyl acrylate-co-methacrylic acid） （PTBEM） is chosen as a molecular carrier for the incorporation of bis（8-hydroxyquinolate） zinc （Znq2） and open-ring merocyanine （MC） （denoted as （Znq2/MC）@PTBEM）. Alternatively, electrostatic assembly is performed with cationic layered double hydroxide （LDH） nanosheets （denoted as [（Znq2/MC）@PTBEM/LDH]n）. This [（Znq2/MC）@PTBEM/ LDH]n system offers a multi-dimensional propagation medium and ensures that the FRET donor and acceptor are located within their F6rster radii in each direction. The system demonstrates a FRET process that can be switched via alternating ultraviolet/visible （UV/vis） irradiation, with tunable blue-green/red fluorescence, resulting in a FRET efficiency as high as 81.7%. It is expected that this assembly method, which uses 0D micelles on a 2D layered material, can be extended to other systems for further development of multi-dimensional FRET.

Ce-doped Zn-Al layered double hydroxide（LDH） nanocontainer was synthesized by a co-precipitation method. X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FT-IR）, scanning electron microscopy（SEM） and transmission electron microscopy（TEM） methods were used for the characterization of the LDH nanocontainer. The anticorrosion activity of the LDH powders embedded in a hybrid sol-gel coating on aluminum alloy 2024 was investigated by electrochemical impendence spectroscopy（EIS）. The results showed that Ce（III） ions were successfully incorporated into LDHs layers. The sol-gel coating modified with Ce-doped Zn-Al LDHs exhibited higher anticorrosion behavior compared with both unmodified and Ce-undoped LDHs containing coatings, which proved the applicability of Ce-doped LDHs in delaying coating degradation and their potential application as nanocontainers of corrosion inhibitors in self-healing coatings.

A superhydrophobic surface was successfully constructed to modify the layered double hydroxide （LDH） coatings on aluminum alloy using stearic acid. The characteristics of the coatings were investigated using SEM, XRD, FT- IR and XPS. The corrosion resistance of the prepared coatings was studied using potentiodynamic polarization and electrochemical impedance spectrum. The results revealed that the superhydrophobic surface considerably improved the corrosion-resistant performance of the LDH coatings on the aluminum alloy substrate. The formation mechanism of the superhydrophobic surface was proposed.

The adsorbing effect of calcined layered double hydroxide （CLDH） for chloride ions in simulated concrete pore （SCP） solutions was investigated with the potentiodynamic polarization method, impedance measurement, ion selective electrode analysis and XRD. CLDH could effectively adsorb Cl^- and increase pH value in SCP solutions containing NaCl. The chloride to hydroxyl ions ratio （[C1^-]/[OH^-]） of the solution greatly decreased by CLDH treatment. In CLDH treated SCP solution with CI-, the pitting potential of carbon steel notably increased, and the surface impedance was much higher, indicating strengthened passivation. The process of CLDH adsorbing chloride ions from SCP solutions was accompanied with the reconstruction of the layered structure.

The increasing importance of the ecologically minded production of building materials makes it necessary to develop reasonable alternatives to the CO2-intense production of ordinary Portland cement （OPC）. The development of new or modified concrete is an important part of existing strategies to improve performance and minimize life-cycle costs. Therefore, we investigated carbonation resistance properties of sulphoaluminate cement （SAC） concrete incorporating layered double hydroxides （LDHs）. X-ray diffraction （XRD） and IR-spectroscopy were employed to characterize the component and structural changes of LDHs and cement paste before and after carbonation test. Carbonation resistance of concrete was experimentally evaluated. Finally, carbonation of Portland cement and SAC concrete was compared. The experimental results show that carbonation depth decreases remarkably with the addition of LDHs, especially the calcinated LDHs. Carbonation depth of SAC concrete is smaller than that of PC concrete regardless of curing time.

Dynamic rheological properties of asphalt modified by Supramolecular UV resistant material—layered double hydroxides（LDHs） was studied by means of the dynamic shear rheometer（DSR） test.Two typical base asphalts were chosen and modified by 2 different LDHs contents.DSR tests were performed on the original samples,samples after exposed to outdoor and samples after the artificial accelerated UV aging tests respectively to analyze the rheological properties.It is found that when the LDHs content is between 3wt% and 5wt% of asphalt weight,the high temperature performance and fatigue resistant property of the modified asphalt become better,the UV aging resistance properties are improved.

Layered double hydroxides （LDHs）/styrene-butadiene-styrene （SBS） eopolymer modified bitumen was prepared by melt blending. The effect of LDHs on the ultraviolet （UV） aging behavior of SBS modified bitumen was investigated. The changes of chemical structures of modified bitumen before and after UV aging were characterized by Fourier transform infrared spectroscopy （FTIR）. The results show that LDHs obviously reduce the variation of softening point and low temperature flexibility of SBS modified bitumen under different UV radiation intensities, which indicates that the UV aging resistance performance of SBS modified bitumen is improved effectively by LDHs. Compared with SBS modified bitumen, the changes of carbonyl, sulfoxide and butadienyl of LDHs/SBS modified bitumen decrease significantly after UV aging according to FTIR analysis, demonstrating that the oxidation and degradation reactions of SBS modified bitumen were restrained effectively by adding LDHs.