Facile in situ synthesis of flexible porous polycarbazole/BCN nanocomposite as a novel electrode material for high-performance supercapacitor

Incorporation of novel 2D materials with conducting polymers have attracted increasing attention in the supercapacitor applications owing to their unique properties. In the present work, novel polycarbazole (PCz)/porous boron carbon nitride (BCN) nanocomposites were prepared in different ratio (30, 50, and 70 wt%) via facile in situ chemical oxidative polymerization method. The PCz-BCN nanocomposites was synthesized at room temperature using an easy and inexpensive chemical oxidative method. The structure and formation of nanocomposites were analysed by X-ray diffraction (XRD), Fourier Transform Infra-Red (FT-IR), Raman Spectroscopy, and X-ray Photoelectron Spectroscopy (XPS) characterization techniques. Furthermore, the structural morphology of the PCz-BCN nanocomposite-50 wt% was analysed by Field Emission-Scanning Electron Microscopy (FE-SEM) and High-Resolution Transmission Electron Microscopy (HR-TEM). The thermal behaviour of the as-prepared sample was analysed using Thermo Gravimetric Analysis (TGA) technique. Cyclic Voltammetry (CV), Galvanostatic Charge-Discharge (GCD), and Electrochemical Impedance Spectroscopy (EIS) studies were used to evaluate the electrochemical specific capacitive performance of the prepared electrode material at different scan rates and current density in the various potential windows. It was found that the orthorhombic crystalline nature of the polycarbazole incorporated well with the stacking layer of the sp(2)-hybridized graphitic BCN aromatic ring structure via the Van der Waals interaction. The PCz/BCN-50 wt% nanocomposite electrode material exhibits specific capacitance 134 F g(-1) at current density of 3 mA g(-1) in aqueous electrolyte 3 M KOH compared to the pure PCz and BCN. Furthermore, even after 800 cycles, the PCz-BCN nanocomposite electrode demonstrated excellent cyclic stability, because the improved enhancement of the specific capacitance of the conductive network of the PCz-BCN composite, as well as the synergistic effect of pure PCz and BCN, makes it a promising material for supercapacitor application. Hence, the facile in situ oxidative polymerization method of the synthesis of the porous PCZ-BCN nanocomposite is a promising route for producing electrode materials so as to fabricate high-performance supercapacitors in a cost-effective way.