Figure 1. Schematic diagram of the formation process of CoN-Ni3N/N-C/CC, VN/CC, and the assembly of the flexible quasi-solid-state asymmetric supercapacitor device. Credit: LI Kunzhen

Recently, a research team led by Prof. Zhao Bangchuan from the Institute of Solid Materials of the Hefei Institutes of Physical Science (HFIPS) synthesized 3D porous honeycomb-like CoN-Ni3N/N-C nanosheets and vanadium nitride (VN) nanobelt arrays via in-situ growth method, respectively, and constructed a high-energy-density flexible supercapacitor device. The result has been published in Advanced Functional Materials.

Transition metal nitrides (TMNs) are potential electrode materials for high-performance storage devices, but the structural instability severely hinders their application. Therefore it is urgent to construct advanced cathode materials for flexible, wearable, long-life and high-energy-density energy storage devices.

In this research, scientists designed and fabricated an integrated cathode with 3D porous honeycomb-like CoN-Ni3N/N-C nanosheets, which were grown on flexible carbon cloth (CC) via a mild solvothermal method after post-nitrogenizing treatment.

Further experiments proved that the intrinsic conductivity was enhanced, and concentration of the active sites was increased. It gives advantage to the optimized CoN-Ni3N/N-C/CC, which can be used as an integrated electrode for the to achieves remarkable electrochemical performance.

This supercapacitor delivers an excellent energy density of 106 μWh cm2 with maximum power density of 40 mW cm2, displaying an outstanding cycle stability.

This work provides a viable strategy to construct high-energy flexible wearable electronics in next-generation electrochemical energy field.

Figure 2. SEM images of (a-c) Co-Ni LDH/CC, (d-f) CoN-Ni3N/N-C/CC, and (g-i)VN/CC at different magnification. Credit: LI Kunzhen

More information: Kunzhen Li et al, 3D Porous Honeycomb‐Like CoN‐Ni 3 N/N‐C Nanosheets Integrated Electrode for High‐Energy‐Density Flexible Supercapacitor, Advanced Functional Materials (2021). DOI: 10.1002/adfm.202103073

Journal information: Advanced Functional Materials