Mn₂P₂O₇–polyaniline hybrid composite as a promising electrode material for advanced symmetric supercapacitors

The development of advanced electrode materials with superior electrochemical performance is imperative to meet the growing demands of modern energy storage technologies. In this study, we report a novel Mn₂P₂O₇-polyaniline (PMP) nanohybrid synthesized <i>via in situ</i> oxidative polymerization of aniline onto hydrothermally prepared Mn₂P₂O₇ (MP) nanoclusters. The resulting materials were thoroughly characterized using structural, morphological, chemical, and elemental analysis techniques. The electrochemical behavior of the PMP nanohybrid was systematically investigated and compared with the pristine MP electrode. The PMP electrode exhibited substantial enhancement in performance, achieving a 1.78-fold increase in specific capacity, a 44% improvement in rate capability at 20 A g^-1, and excellent cycling stability. Notably, a symmetric supercapacitor device assembled using PMP delivered a high energy density of 79.1 Wh kg^-1 at a power density of 749.3 W kg^-1 while retaining 90.5% of its initial capacity after 10 000 GCD cycles, underscoring its outstanding long-term durability. These findings demonstrate that the PMP nanohybrid offers a promising strategy for engineering high-performance, stable, and sustainable supercapacitor devices, paving the way for practical applications in next-generation energy storage systems.