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[Display omitted] • A ternary ZnMgAl-LDH@Fe 2 O 3 /3DHPCNF were successfully prepared. • The electrode showed excellent electrochemical activity as both anode and cathode. • The structural and electrochemical effect of Zn has been studied in detail. • The optimized ZnMgAl-LDH@Fe 2 O 3 /3DHPCNF has yielded capacity of 3437 mF cm−2. • The supercapacitor device delivered high energy density of 11.622 mW cm−3 at 9.999 mW cm−3. Nano confinement of Layered double hydroxide (LDHs) nanosheets and metal oxide is a compelling way to develop new functional materials with unique physiochemical features for various energy storage devices with enhanced performance. Herein, ternary zinc-magnesium-aluminum layered double hydroxide (ZMA-LDH) nanosheets and hematite (α-Fe 2 O 3) nanorods are confined in a hetero-interfacial orientation on electrospun three-dimensional hollow and porous carbon nanofibers (3DHPCNF) by a subsequent hydrothermal process, resulting in the formation of a multi-dimensional nanoarchitecture. Such a structure can incorporate a conductive matrix and eliminate the need of current collectors, thereby minimizing the dead mass in electrochemical energy storage materials. The amount of Zn significantly determines the structural, morphological, and electrochemical properties of ZMA-LDH nanostructures. ZMA-LDH@Fe 2 O 3 /3DHPCNF was used as a free-standing electrode material for supercapacitors and endowed high capacitive behavior at both positive and negative working potentials. With the well-arranged 1D-3D hollow and porous interconnection, increased terrestrial surface area, and superior electrical conductivity, the hierarchical composite electrode offers a high areal capacitance of 3437F cm−2 at 1 mA cm−2 and ultrahigh cyclic stability. This fascinating electrochemical performance is attributed to the synergistic effect of 1D/2D/3D hollow and porous nanostructures, bimetallic compositions, top-to-bottom utilization of electrode materials, and unique combinations of surface interfacial diffusion and faradaic reduction governed by carbon and LDH/Fe 2 O 3 , respectively. Furthermore, a flexible all solid-state ZMA-LDH@Fe 2 O 3 /3DHPCNF symmetric supercapacitor exhibited a high areal energy density at a high power density along with excellent cyclability. This result suggests new prospects to design highly efficient multi material based electrodes for energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel MOF derived Co-Al-LDH@Fe 2 O 3 /3DPCNF adsorbents was synthesized. • The hybrid nanocomposites showed excellent adsorption capacities on Cr(VI) and Pb(II). • The adsorption isotherm, kinetics, thermodynamics, and mechanism were discussed in detail. • The composite can be easily recovered by magnet after adsorption process. Metal organic framework (MOF) derived layered double hydroxide (LDHs) are not properly probed in the field of the heavy metal ions adsorption from its aqueous solution, although they demonstrated a high possibility in adsorption. In this report, a Co-Al layered double hydroxide loaded with hematite (α-Fe 2 O 3)@3D porous carbon nanofiber (Co-Al-LDH@Fe 2 O 3 /3DPCNF) was synthesized by a sequential hydrothermal process. The Co-Al LDH was derived from a Co-metal organic framework. FE-SEM, TEM, FTIR, XPS, and BET characterizations and Cr(VI) and Pb(II) adsorption capacities of the composites were investigated in detail. The super hydrophilic Co-Al-LDH@Fe 2 O 3 /3DPCNF exhibited superfast removal efficiencies for Cr(VI) and Pb(II) with maximum adsorption capacities of 400.40 mg g−1 and 426.76 mg g−1, respectively. Precipitation, surface complexation, isomorphic substitution, and electron transfer were considered to be the main adsorption mechanisms. Adsorption isotherms were well fitted using the Sips model, and the adsorption thermodynamics demonstrated that the adsorption process is endothermic and spontaneous. The Co-Al-LDH@Fe 2 O 3 /3DPCNF maintained excellent adsorption capacity after ten cycles. The present study provides a new pathway to significantly improve the adsorption performance and stability of LDHs with easy separation from water body. [ABSTRACT FROM AUTHOR]