Magnesium Hydroxide Templated Hierarchical Porous Carbon Nanosheets as Electrodes for High-Energy-Density Supercapacitors

Abstract

Hierarchical porous carbon nanosheet (HPCN) materials of different thicknesses were fabricated on Mg(OH) 2 substrates utilizing a one-step chemical vapor deposition (CVD) approach. The templated carbon nanosheets are closely packed hierarchical nanostructures possessing high surface areas varying from 1323 to 1978 m 2 •g −1 . Symmetrical electrochemical doublelayer capacitors (EDLCs) were constructed using the HPCN and demonstrated a high specific capacitance of 205 F•g −1 at 5 mV/s using 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide (EMIM-TFSI) as an electrolyte. The energy density was 86 Wh•kg −1 , and a power density of up to 16.57 kW•kg −1 was observed. After 5000 charge−discharge cycles at 10 A•g −1 , the supercapacitor retained 90% of its initial capacity. This illustrates the great stability of the templated mesoporous carbon sheets for supercapacitors.

Carbon fiber composite electrodes derived from metal organic polyhedra-18 and matrimid for hybrid supercapacitors

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Toward three-dimensionally ordered nanoporous graphene materials: template synthesis, structure, and applications

“…For practical industrial applications, HF should be replaced with the less hazardous HCl. Catalytically active MgO 105–107 is a promising template material 24,108,109 that does not require HF during template etching. Investigating the dissolution of ANPs and zeolites in benign and safe ways is crucial for the practical application of NPGs.…”

Dual‐template synthesis of hierarchical porous carbon and its application in electrical double‐layer capacitors

“…[12] To meet the needs of high surface area and rapid ion diffusion, it is crucial to synthesize the hierarchical porous carbons (HPCs) with a reasonable ratio of micropore to mesopore for the EDLCs. Synthesis of HPCs mainly includes activation method, [14][15][16] template method, [17][18][19] and a combination of template and activation method. [20,21] Among the above methods, the template method is the most popular because it can precisely control the pore size.…”