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Synthesis of high-concentration B and N co-doped porous carbon polyhedra and their supercapacitive properties

Taking phenylboronic acid as a boron source and ZIF-11 as a carbon template, boron and nitrogen co-doped porous carbon polyhedra (BN-PCPs) were prepared through a simple procedure for the first time. The as-prepared BN-PCPs were characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and typical electrochemical methods. The results show that the developed BN-PCPs possess 10.68 atom% B and 8.1 atom% N with uniform distribution, and excellent electrochemical capacitive properties with high specific capacitance of 262 F g−1 at 20 mV s−1 in 1.0 M H2SO4 aqueous solution and excellent long-term charge–discharge stability (no obvious degradation during 40 000 charge–discharge cycles at 20 A g−1).