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Origami and layered-shaped ZnNiFe-LDH synthesized on Cu(OH) 2 nanorods array to enhance the energy storage capability. [Display omitted] The combination of layered nanorod arrays with unique core–shell structure and transition metal layered double hydroxide (LDH) is considered as a feasible solution to improve the electrochemical performances of capacitor electrode. In this study, layered ZnNiFe-LDH@Cu(OH) 2 /CF core–shell nanorod arrays, which consist of ultrathin ZnNiFe-LDHs nanosheet shells and ordered Cu(OH) 2 nanorod inner cores, are successfully designed and fabricated by a typical hydrothermal way and a simple in situ oxidation reaction. The electrode prepared using ZnNiFe-LDH@Cu(OH) 2 /CF nanomaterial reveals an remarkable area capacitance of 6100 mF cm−2 at 3 mA cm−2 current density, which is excellently superior than those of ZnFe-LDH@Cu(OH) 2 /CF, NiFe-LDH@Cu(OH) 2 /CF, Cu(OH) 2 /CF and CF. Additionally, the capacitance retention remains as high as 83.4% after 5000 cycles and a very small Rs (0.567 Ω) can be observed. In addition, an asymmetric supercapacitor device is successfully fabricated employing ZnNiFe-LDH@Cu(OH) 2 /CF. Meanwhile, the ZnNiFe-LDH@Cu(OH) 2 /CF//AC device can achieve an energy density of 44 Wh kg−1 and a corresponding power density of 720 W kg−1 and possess the capability to light up a multi-function monitor for 33 min just using two ASC equipments connected in series. Therefore, the prepared ZnNiFe-LDH@Cu(OH) 2 /CF composite materials with unique structure has great application potential in energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Ortho-hexagonal and highly-oriented NiMnCo-LDH/ZnO@CC self-supporting electrode derived from ZIF-67 covered ZnO nanorod-arrays is fabricated and employed for portable asymmetric solid-state supercapacitor. • Novel ortho -hexagonal NiMnCo-LDH has been synthesized. • ZIF-67 covered ZnO nanorod-arrays as self-supporting electrode is synthesized. • The fabricated electrodes exhibit superior electrochemical properties. • A multifunctional instrument can be powered for more than 30 mins. • The device can be carried outdoors to monitor time, temperature and air humidity. Metal-organic frameworks have attracted much attention due to their abundant redox sites and tunable characteristics, which are advantageous for energy storage applications. However, the low electrical conductivity, poor physical strength and undesirable capacity seriously hinder their applications. Therefore, designing effective and convenient strategies to build composites with unique structures will be of practical significance. Herein, we successfully generate NMC-LDH/ZnO@CC nanocomposites by growing ortho -hexagonal nickel–cobalt layered double hydroxide (NMC-LDH) nanosheets in-situ on ZIF-67 precursor covering vertical arrays of ZnO nanorods. As a result of the unqiue ortho -hexagonal structure, highly ordered arrangement of active substances and multi-dimensional spaces of the prepared NMC-LDH/ZnO@CC binder-free electrode, its capacitance is as high as 9258 mF cm−2 at a current density of 2 mA cm−2 and the capacitance retention is maintained at 87.5 % after 5000 cycles. Furthermore, in order to explore the practical value of the prepared binder-free electrode, the NMC-LDH/ZnO@CC//AC solid-state asymmetric supercapacitor device is assembled. The energy density of the assembled supercapacitor is 24.6 W h kg−1 at a power density of 170 W kg−1 and 1020 W kg−1 at an energy density of 11.8 W h kg−1. In addition, a versatile instrument for monitoring air humidity, time and ambient temperature in portable environments can be powered by a single ultracapacitor unit for more than 30 min. Overall, this study provides a unique strategy for synthesizing ZIF derivatives with novel morphologies for electrochemical energy storage applications. [ABSTRACT FROM AUTHOR]