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

• Published in: Carbon (New York) 2019-04, Vol.144, p.540-548
• Main Authors: Li, Zuo-Xi, Yang, Bo-Long, Zou, Kang-Yu, Kong, Lingjun, Yue, Man-Li, Duan, Hui-Hui
• Format: Article
• Language: English
• Subjects: 2D MOF precursors; Activated carbon; Activated porous carbon; Alternative energy sources; Capacitance; Composite materials; Electrochemical double layer capacitors; Flux density; Morphology; Nanosheets; Porosity; Supercapacitors; Symmetric supercapacitor cells
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2018.12.061

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 m2 g−1) and pore volume of 1.50 cm3 g−1 (Vmirco = 0.12 cm3 g−1, Vmeso+macro = 1.38 cm3 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/cm2. SSC based on APC achieves excellent specific energy density of 18.38 W h 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. One novel 2D Cu-MOF is employed as a precursor to prepare the APC nanosheet with interspace through the calcination-thermolysis strategy, which presents ultrahigh BET specific surface area and excellent supercapacitance. Furthermore, SSC based on the APC nanosheet shows remarkable energy density under high power density, and a red LED can be lighted up by three SSCs over 12 min. [Display omitted]