Novel porous carbon nanosheet derived from a 2D Cu-MOF: Ultrahigh porosity and excellent performances in the supercapacitor cell

摘要

In this work, a novel Cu-MOF of translational 2D (4,4) layers has been designed and afforded as hierarchically stacking lamellae with interspace. Cu-MOF is initially employed as precursors to prepare the Cu@C composite through calcination-thermolysis procedure. Then Cu@C is etched with HCl, and subsequently activated by KOH to obtain APC with nanosheet morphology, which shows ultrahigh BET specific surface area (2491 m(2) g(-1)) and pore volume of 1.50 cm(3) g(-1) (V-mirco = 0.12 cm(3) g(-1), Vmeso+macro = 1.38 cm(3) g(-1)). Significantly, the APC nanosheet owns outstanding specific capacitance of 260.5 F g(-1) at 0.5 A g(-1) under a load of 8 mg/cm(2). SSC based on APC achieves excellent specific energy density of 18.38 Wh Kg(-1) at specific power density of 350 W kg(-1). Our SSC still retains 91.1% of original capacitance after 5000 cycles, exhibiting remarkable long-term cycle and reversibility. Amazingly, a red LED can be lighted up by three SSCs over 12 min. Therefore, the APC nanosheet is a competitive and promising candidate for preparing supercapacitor cells. (C) 2018 Elsevier Ltd. All rights reserved.