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[Display omitted] Two dimensional (2D) materials, with ideal interlayer spacing for ion intercalation/de-intercalation, are quite appealing for hybrid supercapacitors (HSCs) in the pursuit of harvesting promising electrochemical performance. Integrating different 2D materials together is one effective strategy to achieve such goals. However, preserving the ion diffusion channel and accelerating electron transfer should be considered during the compositing process. Herein, we propose a two-step strategy to efficiently composite cobalt hydroxide (Co(OH) 2) and Ni-based MOF (Ni-MOF-24), in which a vertically oriented Ni-MOF@Co(OH) 2 array on nickel foam is obtained. The maximum specific capacitance of 1448 Fg−1 (2 Ag−1) is delivered by Ni-MOF@Co(OH) 2. Accordingly, a hybrid Ni-MOF@Co(OH) 2 //AC HSC is thereof assembled, which outputsa high specific power of 22,400 W kg−1 and a considerable specific energy of 45.7 Wh kg−1. [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs) with numerous potential pseudocapacitive sites are quite appealing to supercapacitors with high specific and areal capacitances. However, MOFs suffer from a low conductivity nature, resulting in a mediocre electrochemical performance. Herein, we propose a template-growth strategy of MOF to enhance both specific and areal capacitances of MOF as the electrode material for supercapacitor. As the loading mass of MOF increases from 2 to 5 mg, the specific capacitance also increases from 937 to 2387 Fg−1 (431 to 1098 Cg−1) and areal capacitance 1.87 to 11.94 Fcm−2 (0.86 to 5.49 Ccm−1). Accordingly, a hybrid MOF//AC supercapacitor can deliver a maximum energy density of 67 Wh kg−1 and a maximum power density of 6000 W kg−1. These results point to a way to fabricate MOF electrode of supercapacitor with high specific and areal capacitance, which leads them to a more practical future. [ABSTRACT FROM AUTHOR]

Abstract: Metal organic frameworks (MOFs) are considered as promising candidates for supercapacitors because of high specific area and potential redox sites. However, their shuffled orientations and low conductivity nature lead to severely‐degraded performance. Designing an accessibly‐manipulated and efficient method to address those issues is of outmost significance for MOF application in supercapacitors. It is the common way that MOFs scarify themselves as templates or precursors to prepare target products. But to reversely think it, using target products to prepare MOF could be the way to unlock the bottleneck of MOFs' performance in supercapacitors. Herein, a novel strategy using Co(OH)2 as both the template and precursor to fabricate vertically‐oriented MOF electrode is proposed. The electrode shows a double high specific capacitance of 1044 Fg−1 and excellent rate capability compared to MOF in powder form. An asymmetric supercapacitor was also fabricated, which delivers a maximum energy density of 28.5 W h kg−1 at a power density of 1500 W kg−1, and the maximum of 24000 W kg−1 can be obtained with a remaining energy density of 13.3 W h kg−1. Therefore, the proposed strategy paves the way to unlock the inherent advantages of MOFs and also inspires for advanced MOF synthesis with optimum performance. [ABSTRACT FROM AUTHOR]