Boron and nitrogen co-doped double-layered mesopore-rich hollow carbon microspheres as high-performance electrodes for supercapacitors

摘要

In this paper, double-layered mesopore-rich hollow carbon microspheres (DHCM) were prepared by a Stober method using tetraethyl orthosilicate, resorcinol and formaldehyde as precursor materials, and further utilized as carbon sources to prepare the boron and nitrogen co-doped double-layered mesopore-rich hollow carbon microspheres (B, N-DHCM) by hydrothermal approach utilizing ammonium tetraborate tetrahydrate (NH4B5O8 center dot 4H(2)O) as boron and nitrogen sources. Compared with the undoped DHCM, the as-obtained B, N-DHCM displays improved capacitive properties with a high specific capacitance (221.5 F g(-1) at 1 A g(-1)), good rate performance (104.1 F g(-1) at 20 A g(-1)) and superior cycle life (91% of capacitance retention at 3 A g(-1) after 10,000 cycles). The outstanding capacitive performances result from the synergistic effect of the unique double-layered mesopore-rich hollow structure contributing to the rate property and cycle stability and the modification of B and N co-doping providing pseudocapacitance for the enhancement of specific capacitance. Therefore, the excellent capacitive behaviors render the B, N-DHCM promising electrode materials for application in supercapacitors and other energy storage systems. (C) 2020 Elsevier Inc. All rights reserved.