Kinetics control over the Schiff base formation reaction for fabrication of hierarchical porous carbon materials with tunable morphology for high-performance supercapacitors

Abstract

Schiff base formation reaction is highly dynamic, and the microstructure of Schiff base polymers is greatly affected by reaction kinetics. Herein, a series of Schiff base cross-linked polymers (SPs) with different morphologies are synthesized through adjusting the species and amount of catalysts. Nitrogen/oxygen co-doped hierarchical porous carbon nanoparticles (HPCNs), with tunable morphology, specific surface area (SSA) and porosity, are obtained after one-step carbonization. The optimal sample (HPCN-3) possesses a coral reef-like microstructure, high SSA up to 1003 m2 g−1, and a hierarchical porous structure, exhibiting a remarkable specific capacitance of 359.5 F g−1 (at 0.5 A g−1), outstanding rate capability and cycle stability in a 1 M H2SO4 electrolyte. Additionally, the normalized electric double layer capacitance (EDLC) and faradaic capacitance of HPCN-3 are 0.239 F m−2 and 10.24 F g−1 respectively, certifying its superior electrochemical performance deriving from coral reef-like structure, high external surface area and efficient utilization of heteroatoms. The semi-solid-state symmetrical supercapacitor based on HPCN-3 delivers a capacitance of 55 F g−1 at 0.5 A g−1, good cycle stability of 86.7% after 5000 GCD cycles at 10 A g−1, and the energy density ranges from 7.64 to 4.86 Wh kg−1.

Facile Synthesis and Outstanding Supercapacitor Performance of Ternary Nanocomposite of Silver Particles Decorated N/S Dual-Doped Graphene and MoS2 Microspheres Stabilized by Graphene Quantum Dots

“…By adding appropriate additives, the interfacial tension can be reduced or eliminated, and the dispersion uniformity and performance of the composite can be improved. [44][45][46][47] As a new kind of zero-dimensional materials, graphene quantum dots (GQDs) have good dispersity, stability, quantum confining effect and edge effect. Using GQDs as an interface agent is conducive to the formation of nanocomposite materials of graphene and MoS 2 with stable structure, accelerating electron diffusion and ion transport, and thus facilitate the practical application of graphene composite electrode materials.…”