Ultrathin Hierarchical Porous Carbon Nanosheets for High-Performance Supercapacitors and Redox Electrolyte Energy Storage

作者：Jayaramulu, Kolleboyina; Dubal, Deepak P.; Nagar, Bhawna; Ranc, Vaclav; Tomanec, Ondrej; Petr, Martin; Datta, Kasibhatta Kumara Ramanatha; Zboril, Radek; Gomez-Romero, Pedro^*; Fischer, Roland A.^*

来源：Advanced Materials, 2018, 30(15): 1705789.

DOI：10.1002/adma.201705789

• graphitic nanoporous carbon sheets
• metal-organic frameworks (MOFs)
• morphology control
• supercapacitors
• 2D materials

The design of advanced high-energy-density supercapacitors requires the design of unique materials that combine hierarchical nanoporous structures with high surface area to facilitate ion transport and excellent electrolyte permeability. Here, shape-controlled 2D nanoporous carbon sheets (NPSs) with graphitic wall structure through the pyrolysis of metal-organic frameworks (MOFs) are developed. As a proof-of-concept application, the obtained NPSs are used as the electrode material for a supercapacitor. The carbon-sheet-based symmetric cell shows an ultrahigh Brunauer-Emmett-Teller (BET)-area-normalized capacitance of 21.4 mu F cm(-2) (233 F g(-1)), exceeding other carbon-based supercapacitors. The addition of potassium iodide as redox-active species in a sulfuric acid (supporting electrolyte) leads to the ground-breaking enhancement in the energy density up to 90 Wh kg(-1), which is higher than commercial aqueous rechargeable batteries, maintaining its superior power density. Thus, the new material provides a double profits strategy such as battery-level energy and capacitor-level power density.

• 出版日期2018-4-12