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[Display omitted] Layered double hydroxide (LDH) has been attracted widespread attention in supercapacitor due to their unique layered structure and associated advantages. However, the inherent limitations of low electrical conductivity and reaction kinetics rate of LDH restrict its widespread application. Various modification techniques, such as heterojunction formation, phosphorization and introduction of phosphorus vacancies, are employed to modify LDH with the goal of improving the electrochemical performance. Preparation of composite materials using MoB MBene as conductive template and phosphorization are the effective ways for enhancing the electrical conductivity of electrode materials. MoB MBene is prepared using a modified method that combines NaOH etching and a high-temperature hydrothermal process. The presence of phosphorus vacancy is beneficial for enhancing the kinetics rate during electrode reactions. Through the synergistic effect of various modification methods, MP2 demonstrates an optimal electrochemical performance with a superior specific capacitance of 1731.19F/g (238.28 mAh g−1) at 1 A/g. It also demonstrates an impressive rate capacity of 81.28 % at 10 A/g and maintains a satisfactory capacitance retention of 88.14 % after 5000 cycles. In addition, a fabricated MP2//AC ASC device achieves an impressive energy density of 39.91 Wh kg−1 at the power density of 948.25 W kg−1 and demonstrates satisfactory cycling stability of 78.76 % after 5000 cycles. This work presents a comprehensive framework for analyzing the impact of material structure, components, and crystal phases on energy storage performance. It also examines the regulatory impact of different modification methods on energy storage mechanisms. [ABSTRACT FROM AUTHOR]

In this study, the ultra-thin CoAl layered double hydroxide (LDH) nanosheets with Cl− intercalation were prepared by a hydrothermal method following acid-salt treatment. The morphology, structure and composition information of CoAl LDHs were identified by a variety of characterization methods including SEM, XRD, XPS, FT-IR, and BET. The effects of initial adsorbent concentration, pH, competitive anions, and temperature were also measured. The fitted adsorption curves are matched well with Langmuir isotherm model and pseudo-second-order kinetic model, suggesting that the removal of methyl orange (MO) is governed by monolayer heterogeneous adsorption and chemical adsorption, respectively. The measurements of adsorption capacity at various temperatures revealed that the adsorption process is spontaneous. Co-existing anions have different negative effects on the adsorption capacity. The Co 4 Al 1 -Cl LDH adsorbent shows the maximum experimental and theoretical adsorption capacity of 801.08 and 827.50 mg g−1 (pH = 7 and T = 293 K), respectively. An adsorption mechanism called "ion exchange and expansion-extrusion" is proposed to explain the change of interlayer spacing. These results indicate that a novel avenue for designing LDH-type adsorbent has been proposed with excellent adsorption capacity for anionic dyes like MO. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract NiFe layered double hydroxides nanoflakes decorated montmorillonite (MMT@NiFe LDH) was successfully prepared by a one-pot hydrothermal method. The 2D-2D growth MMT@NiFe LDH was utilized as an effective adsorbent for removal of anionic dye of methyl orange (MO) and cationic dye of methylene blue (MB). The mole ratio of Ni2+/Fe3+ could quite influence the interlayer spacing, surface area per unit charge and the ultrathin hexagonal laminated morphology of NiFe LDH decorated on the surface of MMT. Various characterization techniques were conducted to identify it, such as XRD, FT-IR, TG-DTA, BET, XPS and SEM. Under the optimal conditions, the Langmuir-fitted maximum adsorption capacities for MO and MB are 108.80 mg g−1 and 99.18 mg g−1, respectively. Adsorption kinetics for MO and MB are both verified to be fit in with pseudo-second-order model. This work suggests a facile pathway to synthesize desirable bifunctional adsorbent for cationic and anionic dyes, which provides the potential application for the actual wastewater purification. [ABSTRACT FROM AUTHOR]

Novel three-dimensional (3D) rosette-like carbonate-type Mg-Al layered double hydroxide (MgAl-LDH) hierarchical microstructures were fabricated successfully by a surfactant-assisted coprecipitation method in the presence of hexamethylenetetramine as precipitant, and the morphology-dependent basic catalytic property was exploited. The morphologies of MgAl-LDH aggregates were diversified depending on the synthesis parameters including the type of precipitant, concentration of sodium stearate surfactant, and hydrothermal aging time. Specifically, the morphology of MgAl-LDH particles could change progressively from platelet-like aggregates to rosette-like microspheres with the increasing concentration of sodium stearate. A possible formation mechanism for special 3D flower-like MgAl-LDH microstructures was proposed based on the synergistic effect of precipitant with surfactant. Moreover, the resulting activated rosette-like MgAl-LDH, which was prepared through calcination-rehydration process, showed a higher catalytic activity in the transesterification of tributyrin with methanol, compared with that derived from the conventional platelet-like MgAl-LDH precursor, which was attributed to its higher specific basicity originating from multi-level hierarchical superstructure offering an advantage in contact with more exposed base sites. [ABSTRACT FROM AUTHOR]