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Layered double hydroxide (LDH) materials, especially metal–organic framework (MOF)-derived LDHs, have attracted much attention in electrochemical capacitor applications. However, the construction of porous three-dimensional microsphere architectures with controlled morphology is highly demanded for high-performance supercapacitor electrodes. Thus, a simple and effective strategy is recommended to design and fabricate the well-defined layered structure of LDHs with high performance. In this study, we demonstrate the synthesis of nickel–cobalt-LDHs (NiCo-LDHs) by in-situ etching of the Ni-MOF template at different hydrolysis times. Based on the different characterization results of the sample, a formation mechanism has been proposed in terms of the proton production rate and etching process. As a result of the disparity in the layered structure and the surface area, the electrochemical behavior of the NiCo-LDHs has been altered. The sample NiCo-LDH/10 (prepared after the 10 h reaction) exhibited a high surface area and the large size of LDH sheets on microspheres, which promoted the rapid electrolyte ion transportation for supercapacitors and displayed a maximum specific capacity of 1272 C g–1 at 2 A g–1. In addition, the assembled asymmetric supercapacitor delivered a remarkable energy density of 36.1 Wh kg–1 with an outstanding cyclic stability (103.9% after 5000 cycles). This work establishes an effective strategy to synthesize a well-defined NiCo-LDH structure from the MOF template toward high-performance asymmetric supercapacitors, which could be extended to large-scale preparation of other transition metal-based LDHs from Ni-MOFs.

composite nanospindles (CNS) are synthesized by a simple and cost effective coprecipitation method. CeO 2 /Fe 2 O 3 CNS used as an efficient recyclable photocatalyst for degrading Eosin Yellow (EY) dye under visible light irradiation possess high degradation rate of 98% after 25 min. The estimated electrical energy efficiency of CeO 2 /Fe 2 O 3 CNS shows the consumption of less energy (6.588 kWhm -3 order -1 ) in degrading EY. Besides, the CeO 2 /Fe 2 O 3 CNS exhibits a specific capacitance of 142.6 F g -1 at a scan rate of 5 mV s -1 . Moreover, the composite displays excellent capacitance retention of 94.8% after 1000 cycles. This newly designed CeO 2 /Fe 2 O 3 CNS with enhanced visible light-driven photocatalytic activity and good supercapacitive cycling stability has great potential for use as wastewater treatment and energy storage applications.

The presence of oxygen functional groups in GO enhances the charge storage behavior of Ce-MOF/GO composites for use as supercapacitor electrode materials.

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