Facile Binder-Free Growth of Pd NPs-Poly Benzidine Nanocomposite Onto GO NS/Graphite Electrode as an Active Nanomaterial for High-Performance Supercapacitor

In this study, we present the binder-free synthesis of a Pd nanoparticles (Pd NPs)-polybenzidine (PB) nanocomposite deposited on graphene oxide nanosheets (GO NS) supported by graphite sheets, developed as a supercapacitor electrode. The Pd-PB/GO NS/GS electrode, featuring a porous structure and excellent capacitive properties, was fabricated through the chemical deposition of polybenzidine (PB) chains onto GO nanosheets, followed by the controlled growth of Pd NPs on these polymer chains. The controlled addition of Pd NPs significantly enhanced the electrode’s electrochemical performance. Comprehensive morphological and structural analyses were conducted using ATR-IR, XRD, EDX, FE-SEM, and TEM. SEM and TEM imaging confirmed the successful doping of Pd NPs onto the polybenzidine chains, while ATR-IR, XRD, and EDX verified the successful synthesis of GO nanosheets and their integration with polybenzidine and Pd NPs on graphite sheets. Electrochemical studies revealed a high specific capacitance of 763.88 F g^-1 at 1 A g⁻¹ in 1.0 M H₂SO₄. Furthermore, the electrode's application in a symmetric solid-state supercapacitor device was explored, showing a specific capacitance of 312.5 F g⁻¹ at 0.5 A g⁻¹ and excellent cyclic stability of 86.2% after 5000 GCD cycles.