Highly Graphitized Porous Carbon Microspheres Derived from Copolymer of Glucose and Melamine for Advanced Electrodes

• Published in: Particle & particle systems characterization 2022-06, Vol.39 (6), p.n/a
• Main Authors: Lin, Zhen‐Hang, Li, Xia, Song, Yun‐Fei, Jing, Lai‐Ying, Zhang, Yun‐Qiang, Li, Mei, Cui, Jia‐Xi
• Format: Article
• Language: English
• Subjects: 3D graphite carbon microspheres; Aqueous electrolytes; Carbon; Condensation polymerization; Copolymers; Electrical resistivity; electrochemical performance; Electrode materials; Electrodes; glucose‐melamine; Graphitization; Hydroxymethylfurfural; Melamine; Microspheres; N/O co‐doping; Sulfuric acid; Supercapacitors; Wettability
• ISSN: 0934-0866; 1521-4117
• DOI: 10.1002/ppsc.202200055

The N/O co‐doped hierarchical porous graphitized carbon microspheres (N/O‐PCs) are successfully prepared by condensation polymerization of 5‐hydroxymethylfurfural and melamine, and subsequent KOH activation strategy. The obtained carbon materials have a high specific surface area (1685.58 m2 g–1), rich micro‐ and mesopores, and appropriate pore volume (0.828 cm3 g–1). The degree of graphitization for N/O‐PCs is improved because the ratio of IG and ID increases from 0.88 to 1.03. The layer spacing of the lattice plane (002) for the N/O‐PCs is enlarged, facilitating the transmission of electrolyte ions. The high graphitization degree and enlarged layer spacing bring excellent electrical conductivity and wettability for N/O‐PCs as electrode materials. Besides, owing to the higher N (3.59 at%) and O (12.67 at%) content, the N/O‐PCs show excellent specific capacitances of 412 and 284 F g–1 at the current densities of 1 and 10 A g–1 in 2 m H2SO4 aqueous electrolytes, respectively. Outstanding rate performance (200 F g–1 at 50 A g–1) and ideal cycle stability (>10 000 cycles) are achieved. Moreover, the N/O‐PCs‐based symmetric supercapacitor exhibits an energy density of 9.6 Wh kg–1 at 100.8 W kg–1. Thus, the N/O‐PCs provide the potential for high‐performance supercapacitor electrodes. Glucose melamine resin is synthesized by the polycondensation of 5‐hydroxymethylfurfural and melamine under the regulation of boric acid and sodium dodecyl sulfate. Combined with the subsequent pyrolysis‐activation process, the highly graphitized carbon microspheres with large specific surface area and hierarchical micro/mesopores structure are successfully prepared. Moreover, the expansion of layer spacing could effectively boost electrolyte ion transport and further acquire excellent electrochemistry performances.