Tailoring Interfacial Charge Transport in Polyaniline Through g‐ <scp> C ₃ N ₄ </scp> and <scp> V ₂ O ₅ </scp> Integration for Enhanced Photocatalytic and Dielectric Response

ABSTRACT Polymer‐based composites have emerged as advanced functional materials due to their tunable structural, optical, and electrical properties, which can be achieved through the incorporation of appropriate fillers. In this study, hierarchical polyaniline (PANI)‐based composites incorporating graphitic carbon nitride (g‐C 3 N 4 ) and vanadium pentoxide (V 2 O 5 ) were successfully synthesized using a chemical oxidative polymerization method. The structural, morphological, and optical properties of pristine PANI and its binary and ternary composites were systematically characterized using XRD, FTIR, XPS, FE‐SEM, EDX, HRTEM, and PL analysis. The crystallite size of V 2 O 5 was calculated to be around 20.19 nm using the Debye–Scherrer formula. The photocatalytic performance on crystal violet (CV) dye was evaluated under UV light irradiation. Among all samples, PANI/g‐C 3 N 4 /V 2 O 5 , the ternary composite, exhibited superior activity with a maximum degradation efficiency of 96.63% compared to pure PANI, about 68.08%. The synergistic interaction between PANI, g‐C 3 N 4 , and V 2 O 5 , with effective charge separation and inhibiting the recombination of photogenerated electron–hole pairs, is seen by the markedly decreased PL intensity. Reactive species were identified by trapping experiments as photogenerated holes (h + ) and superoxide radicals (O˙ 2 − ). A plausible photocatalytic mechanism is proposed by calculating band edge potentials. Furthermore, frequency‐dependent AC conductivity and dielectric studies revealed that the composites follow Jonscher's universal power law with S &lt; 1 exhibiting non‐Debye relaxation behavior. Nyquist plots enabled equivalent circuit modeling and provided insights into charge transport mechanisms. Overall, the multifunctional properties of the synthesized composites highlight their potential for efficient water remediation and electronic applications.