Madhusree, J.E.Athulya, K.Chandewar, P.R.Shee, D.Mal, S.S.2026-02-042024ChemistrySelect, 2024, 9, 32, pp. -https://doi.org/10.1002/slct.202401533https://idr.nitk.ac.in/handle/123456789/20973Supercapacitors have emerged as a potential technology in the search for energy storage solutions, delivering astounding performance, environmental sustainability, safety, and economic feasibility. Biomass-derived activated carbon electrodes have received much interest in this area because of their inherent mechanical stability and eco-friendliness. While Wells-Dawson POMs exhibit excellent redox properties for electrochemical performance, however, their solubility nature leads to poor conductivity. Biomass-derived activated carbon was employed as a solid support material to address this issue, which offers high surface area and cost-effectiveness. This work explores the synthesis of new nanofabricated electrodes by adding vanadium-substituted Wells-Dawson polyoxometalates (P<inf>2</inf>VW<inf>17</inf>) to activated carbon derived from lignin (LDAC). In depth, we investigated these novel nanohybrid material's structural properties and electrochemical performance. Furthermore, electrochemical testing was performed for 20 wt % LDAC-P<inf>2</inf>VW<inf>17</inf> in a 0.25 M H<inf>2</inf>SO<inf>4</inf> electrolyte. The 20 wt % LDAC-P<inf>2</inf>VW<inf>17</inf> supercapacitor cell has an excellent specific capacitance of 216.48 F g−1, with great energy and power densities of 30.06 Wh kg−1 and 1999.98 W kg−1. Additionally, it has an excellent capacitance retention of 94.4 % over 4000 cycles with 82.6 % columbic efficiency. A test for practical application has been conducted on 20 wt % LDAC-P<inf>2</inf>VW<inf>17</inf>. The first series of LEDs were connected to the workstation and took hold of 30 seconds to discharge. A piezoelectric buzzer was subjected to a trial as part of our testing procedure. Upon integration with our system, the buzzer produced an audible tone that persisted for 140 seconds. © 2024 Wiley-VCH GmbH.Cyclic stabilityEquivalent circuitHybrid supercapacitorLignin, activated carbon