Hybrid Nanomaterials Based on Polyaniline and Vanadium Oxides: Insights into Synthesis Mechanisms, Morphological Optimization, and Mechanisms of Action – Review

Hybrid organic–inorganic nanocomposites comprising conducting polymers and multivalent transition metal oxides have emerged as pivotal functional platforms across modern electrochemical technologies, high-frequency electromagnetic absorption, and surface protection. Among conducting polymers, polyaniline (PANI) exhibits superior theoretical pseudocapacitance, tunable intrinsic electrical conductivity, and high environmental durability. Nevertheless, the real-world operational capacity of pristine PANI is inherently constrained by severe structural fatigue—manifested as cyclic macromolecular swelling, shrinking, and mechanical degradation—as well as interchain agglomeration. Conversely, layered transition metal oxides such as vanadium pentoxide V₂O₅ and its reduced sub-oxides (VO, V₂O₃ possess layered open crystallographic lattices capable of accommodating multiple intercalation processes via multi-electron redox couples (V⁵⁺,V⁴⁺,V³⁺). Despite these attractive characteristics, pristine vanadium oxides suffer from poor intrinsic electronic conductivity and severe phase dissolution in acidic or aqueous working electrolytes.