Cheng S, Chen B, Qin L, Zhang Y, Gao G, He M. Cross-linked poly(ionic liquid) as precursors for nitrogen-doped porous carbons.
RSC Adv 2019;
9:8137-8145. [PMID:
35518670 PMCID:
PMC9061521 DOI:
10.1039/c8ra10022e]
[Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/06/2019] [Indexed: 01/18/2023] Open
Abstract
A soluble and easily dispersive cross-linked poly(ionic liquid), copolymer of 1-vinyl-3-butylimidazolium bromide ([VBIM][Br]) and divinylbenzene (DVB), was used as a precursor for nitrogen doped porous carbons (NPCs) with SiO2 (from tetraethyl orthosilicate) as a template. The NPCs were characterized by infrared (IR) spectroscopy, nitrogen adsorption–desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, thermo gravimetric analysis (TGA), elemental analysis and X-ray photoelectron spectroscopy (XPS). The specific surface area and porosity of NPCs depended on the carbonization temperature, the SiO2/[VBIM][Br] ratio and the precursors. Under the optimized conditions, the NPC prepared from cross-linked poly(ionic liquid), P([VBIM][Br]–0.1DVB), gave a high specific surface area up to 1324 m2 g−1. XRD indicated that amorphous and disordered graphitic layers were dominant in NPCs. The nitrogen content was about 4–5 wt% in NPCs, and the nitrogen bonding state observed using XPS analysis was mainly pyridinic- and pyrrolic-N. Meanwhile, the cyclic voltammetry, gravimetric charge–discharge curves and electrochemical impedance spectroscopy of the NPCs were also investigated, the specific capacitance was up to 243 F g−1 at 0.1 A g−1, and the retention ratio was nearly 100% after charge–discharge cycling 2400 times at 2 A g−1 in 6 M KOH electrolyte.
The cross-linked PIL with “network structure” can fabricate nitrogen-doped porous carbons with higher specific surface area.![]()
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