Nonylphenol polybenzoxazines-derived nitrogen-rich porous carbon (NRPC)-supported g-C 3 N 4 /Fe 3 O 4 nanocomposite for efficient high-performance supercapacitor application.

In this work, a straightforward and scalable method was used to generate nitrogen-rich porous carbon (NRPC), which was then incorporated with a graphitic carbon nitride and magnetite (g-C ₃ N ₄ /Fe ₃ O ₄ ) nanocomposite, fabricated with Fe ₃ O ₄ nanoparticles as an eco-friendly and economically viable component. The fabricated NRPC/g-C ₃ N ₄ /Fe ₃ O ₄ nanocomposite was applied as an electrode in supercapacitor applications. The synthesized NRPC/g-C ₃ N ₄ /Fe ₃ O ₄ nanocomposite, NRPC, g-C ₃ N ₄ , and Fe ₃ O ₄ were characterized by analytical and morphological analyses. The spherically shaped Fe ₃ O ₄ nanoparticles were analyzed by field-emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM). The specific surface area of NRPC/g-C ₃ N ₄ /Fe ₃ O ₄ was determined to be 479 m ² g ^-1 . All the crosslinked composites showed exceptional electrochemical performance and exhibited a pseudo-capacitance behaviour. In comparison to the Fe ₃ O ₄ and g-C ₃ N ₄ /Fe ₃ O ₄ electrodes, the NRPC/g-C ₃ N ₄ /Fe ₃ O ₄ electrode showed a lower charge-transfer resistance and higher capacitance. The prepared NRPC/g-C ₃ N ₄ /Fe ₃ O ₄ electrode exhibited the highest specific capacitance of 385 F g ^-1 at 1 A g ^-1 compared to Fe ₃ O ₄ (112 F g ^-1 ) and g-C ₃ N ₄ /Fe ₃ O ₄ (150 F g ^-1 ). Furthermore, the cycling efficiency of NRPC/g-C ₃ N ₄ /Fe ₃ O ₄ remained at 94.3% even after 2000 cycles. The introduction of NRPC to g-C ₃ N ₄ /Fe ₃ O ₄ improved its suitability for application in high-performance supercapacitors.