Boron/Nitrogen/Oxygen Co-Doped Carbon with High Volumetric Performance for Aqueous Symmetric Supercapacitors

Abstract

From the practical application of supercapacitors, the development of carbon materials with high volumetric performance is highly desired. We report the synthesis of B/N/O co-doped carbon by a facile one-step carbonization method of polyvinylpyrrolidone/melamine formaldehyde resin with boric acid/urea treatment and a subsequent washing process. It is shown that a boric acid/urea treatment is an effective approach to incorporating B into N/O enriched carbon and effectively restraining the generation of inert B-O and B-N species. Moreover, a boric acid/urea treatment and washing process can increase specific surface area, optimize pore structure, and retain many active heteroatoms without lowering density, contributing to good conductivity, fast charge transfer and electrolyte ion diffusion, and high volumetric performance. The fabricated B/N/O co-doped carbon shows high active heteroatoms of 8.69 at.% (N-5, N-6, B-C and O-I), moderate surface area, and pore volume (778.02 m 2 g −1 and 0.341 cm 3 g −1 ), high density (1.3 g cm −3 ), high specific volumetric, and gravimetric capacitances (309 F cm −3 and 238 F g −1 at 0.5 A g −1 ) and superior cycling stability. The assembled symmetric supercapacitor delivers relatively high volumetric energy density (11.5 Wh L −1 at 622 W L −1 ) in 6 M KOH electrolyte. The B/N/O co-doped carbon has great potential for applications in supercapacitors.

Boron/nitrogen co-doped carbon synthesized from waterborne polyurethane and graphene oxide composite for supercapacitors

“…Especially, WPU-GO-Fe-B exhibited the lowest R s value, resulting from the increase in conductivity and electrochemical activity by the heteroatoms. 26 At low frequency, WPU-GO-Fe-B showed a straight line with the highest slope of nearly 90 to the x-axis, verifying the better capacitive characteristic of WPU-GO-Fe-B (perpendicular line of the ideal capacitor). In addition, the R ct values of WPU-GO, WPU-GO-Fe, WPU-GO-B, and WPU-GO-Fe-B were calculated as 0.81 U, 0.77 U, 0.80 U, and 0.66 U, respectively.…”

“…Fu et al 25 synthesized boron and nitrogen co-doped porous carbon via carbonization with the ferric catalyst treatment from a precursor including nitrogen-containing chitosan and boric acid and an excellent specic capacitance was achieved (313 F g À1 at 1 A g À1 ). Qin et al 26 used polyvinylpyrrolidone, melamine formaldehyde resin, urea, and boric acid to prepare a boron/nitrogen/oxygen co-doped carbon with high capacitive performance (238 F g À1 at 0.5 A g À1 ). The carbon-based materials with different heteroatoms require further improvement in their performance.…”

Highly dispersed Ru nanoclusters anchored on B,N co-doped carbon nanotubes for water splitting

“…Subsequent evaporation of water led to H 3 BO 3 and CH 4 N 2 O covering the surface of the CNTs–COOH. 39 When the previous mixture was heat-treated in the inert atmosphere, the carboxylic acid functionalized CNTs and the coordinated Ru 3+ on them were reduced to a graphitized CNT and Ru nanoclusters, respectively. 40 In the meantime, the H 3 BO 3 and CH 4 N 2 O loaded on the surface of the CNTs–COOH were decomposed, and the partial B and N atoms were also incorporated into the CNTs, giving the target material, Ru@B,N-CNTs.…”

Advanced Materials for Sodium‐Ion Capacitors with Superior Energy–Power Properties: Progress and Perspectives

“…In addition, heteroatom dopants, such as N, O, P acting as electron donor and B serving as electron acceptor elements, can modify the electronic structure of carbon materials and facilitate charge transfer. Furthermore, heteroatom dopants can enhance the capacitance of active materials through pseudocapacitance contribution provided by heteroatom‐containing functional groups . Moreover, the wettability of carbon surface with electrolyte could be improved by the N substitutional doping, which is helpful for improving the electrochemical performance of ACs.…”