Highly efficient and stable layered AgZnS@WS2 nanocomposite electrode as superior charge transfer and active redox sites for energy harvesting device
Asad Ur Rehman, Amir Muhammad Afzal, Muhammad Waqas Iqbal, Muhammad Ali, Saikh Mohammad Wabaidur, Essam A. Al‐Ammar, Sohail Mumtaz, Eun Ha Choi
Abstract
Transition metal dichalcogenides (TMDs) are considered to be excellent candidates in energy storage applications because of their 2D structure and astonishing electrochemical features. Still, the poor stability of these materials limits their way to becoming perfect supercapattery electrode materials. Therefore, researchers are synthesizing their hybrids with other electrode materials to minimize these drawbacks. Herein, the tungsten disulfide (WS 2 ) nanosheets were combined with hydrothermally synthesized silver zinc sulfide (AgZnS) nanostructures to design a hybrid electrode material for high-performance energy storage devices with superior charge transfer and abundant active redox sites. The highly porous structure of AgZnS@WS 2 was analyzed by BET which confirmed the enhancement in ion diffusion and the reversible redox mechanism. The composite was analyzed using SEM, XRD , RAMAN, and XPS to study its morphological, structural, and compositional properties. The effect of different electrolytes was studied to estimate the electrochemical characteristics. The AgZnS electrode, upon characterization in 1 M KOH, revealed the maximum specific capacity (Q s ) of 1209.06 Cg −1 at 1.8 Ag −1 . While the AgZnS@WS 2 hybrid electrode exhibited the Q s of 2516.58 Cg −1 at the same current density (j s ) benefitting from the features of both materials. The AgZnS@WS 2 hybrid electrode employed in a supercapattery revealed a maximum Q s of 388.8 Cg −1 at 1.2 Ag −1 . The device delivered a maximum energy density of 86.4 Wh kg −1 and a notable power density of 4987.6 W kg −1 . The superb 95 % cycle stability and strong electrochemical performance of AgZnS@WS 2 are the results of the highly conductive structure and synergistic effect of hybrid material for high surface area with quick ion diffusion. The astonishing features of hybrid material are suitable and encouraging for its industrial applications as supercapattery electrode material.