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Metal organic frameworks (MOFs) are expected to be promising pseudocapacitve materials because of their potential redox sites and porous structures. Nevertheless, the conductivity inferiority of MOF strongly decreases their structural advantages, therefore resulting in unsatisfying electrochemical performance. Herein, we propose an efficient strategy to enhance conductivity and thus electrochemical properties, in Ni(OH)2 is electrochemically deposited on carbon nanowalls as the precursor for oriented MOF. The synthesized vertically oriented MOF sheets show an almost triple high capacitance of 677 F g−1 than MOF powder of 239 F g−1 at the current density of 2 A g−1. Correspondingly, an asymmetric supercapacitor is fabricated, which can deliver a maximum energy density of 20.7 Wh kg−1 and a maximum power density of 23 200 W kg−1. These promising results indicate that modulating the conductivity of MOF is the key step to pursuit upgrading electrochemical performance. [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]