Design of XS 2 (X = W or Mo)-Decorated VS 2 Hybrid Nano-Architectures with Abundant Active Edge Sites for High-Rate Asymmetric Supercapacitors and Hydrogen Evolution Reactions

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2023-02, Vol.19 (8), p.e2205881
• Main Authors: Hussain, Sajjad, Vikraman, Dhanasekaran, Sarfraz, Maria, Faizan, Muhammad, Patil, Supriya A, Batoo, Khalid Mujasam, Nam, Kyung-Wan, Kim, Hyun-Seok, Jung, Jongwan
• Format: Article
• Language: English
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202205881

Two-dimensional layered transition metal dichalcogenides have emerged as promising materials for supercapacitors and hydrogen evolution reaction (HER) applications. Herein, the molybdenum sulfide (MoS )@vanadium sulfide (VS ) and tungsten sulfide (WS )@VS  hybrid nano-architectures prepared via a facile one-step hydrothermal approach is reported. Hierarchical hybrids lead to rich exposed active edge sites, tuned porous nanopetals-decorated morphologies, and high intrinsic activity owing to the strong interfacial interaction between the two materials. Fabricated supercapacitors using MoS @VS  and WS @VS  electrodes exhibit high specific capacitances of 513 and 615 F g , respectively, at an applied current of 2.5 A g  by the three-electrode configuration. The asymmetric device fabricated using WS @VS  electrode exhibits a high specific capacitance of 222 F g  at an applied current of 2.5 A g  with the specific energy of 52 Wh kg  at a specific power of 1 kW kg . For HER, the WS @VS  catalyst shows noble characteristics with an overpotential of 56 mV to yield 10 mA cm , a Tafel slope of 39 mV dec , and an exchange current density of 1.73 mA cm . In addition, density functional theory calculations are used to evaluate the durable heterostructure formation and adsorption of hydrogen atom on the various accessible sites of MoS @VS  and WS @VS  heterostructures.