Three-dimensional hierarchical carbon architecture of porous carbon derived from cross-linked polycyclophosphazenes as supercapacitor electrode material

Polyphosphazenes (PPNs) belong to a well-known class of organic-inorganic hybrid materials (HMs) with tunable morphologies, hierarchical porous structure, and extrinsic and intrinsic co-doping of binary, ternary, and quaternary heteroatom functionalities, like nitrogen, phosphorous, oxygen, and sulfur, and with exceptional structural stability imparted by (-P = N-) inorganic backbone. Herein, three-dimensional hierarchical carbon architecture (3D-HCA) is successfully synthesized from poly(cyclotriphosphazene-co-4,4'-sulfonyl-biphenol) (PZS) and trithiocyanuric acid (TTCNA). The PZS@TTCNA is fabricated via sono-thermal co-precipitation method using acetonitrile (ACN) solvent; the final product was pyrolyzed at high temperature and KOH activation to convert into co-doped carbon material. This co-doped carbon material is characterized using Raman spectroscopy, X-ray diffraction powder method (XRD), and scanning electron microscopy. The 3D-HCAderived carbon material is utilized as cathode material for supercapacitor application; the hierarchical porous interconnected layers of active carbon material have more active sites and play a dominant role in ion transport between the co-doped carbon and electrolyte ( H2SO4 1 mol/L). PZS@TTCNA delivers a capacitance of 244 F/g at a current density of 0.1 A/g. This study unfolds a new approach to develop 3D-HCA from PZS@TTCNA and can be a promising electrochemical material for energy storage applications.