Green synthesis of N-doped porous carbon/carbon dot composites as metal-free catalytic electrode materials for iodide-mediated quasi-solid flexible supercapacitors

Publication Name

Inorganic Chemistry Frontiers


P-Nitroaniline has been adopted as a versatile precursor for the selective preparation of N-doped porous carbon (PC) and carbon dots (CDs) with rich N functionalities. Furthermore, the CDs are anchored on PC to yield PC-CDs composites with the assistance of ultrasonication. Due to the catalytic effect of the pyridinic- and pyrrolic-N sites within the CDs as well as the high specific surface area and conductivity of PC, the optimized PC-CDs-1.5% composite (containing 1.5% CDs) could substantially promote the redox reaction of the acidic KI electrolyte. Therefore, the PC-CDs-1.5%-based supercapacitor demonstrated high specific capacitance (Cs, 1783 F g−1 at 1 A g−1), good rate capability (800 F g−1 at 6 A g−1) and excellent cycling stability (84.7% Cs retention upon 10 000 charge-discharge cycles). Moreover, when employed as the electrode in a flexible supercapacitor, the PC-CDs-1.5% composite also exhibits good capacitive performance in the PVA-H2SO4-KI gel electrolyte, and a high energy density (Ecell) of 13.85 W h kg−1 at a power density (Pcell) of 97.00 W kg−1 is also delivered. In addition, the flexible device shows good electrochemical cycling stability and the Cs of the flexible device could be well maintained under bending and twisting deformations.

Open Access Status

This publication is not available as open access

Funding Number


Funding Sponsor

National Natural Science Foundation of China



Link to publisher version (DOI)