Wells‐Dawson Polyoxometalate Modified Lignin Derived High Surface Area Activated Carbon Electrode Materials for Energy Storage Application

Abstract Supercapacitors 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 2 VW 17 ) 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 2 VW 17 in a 0.25 M H 2 SO 4 electrolyte. The 20 wt % LDAC‐P 2 VW 17 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 2 VW 17 . 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.