Speaker
Description
The increasing demand for advanced energy storage systems has stimulated significant
research interest in developing electrode materials with enhanced charge storage
capability and excellent long-term cycling stability. Molybdenum disulfide (MoS₂), a
layered transition metal dichalcogenide (TMD), has attracted considerable attention in
recent years owing to its unique layered structure and intrinsic pseudocapacitive
characteristics [1]. However, the practical electrochemical performance of pristine MoS₂
is limited by its low electrical conductivity and relatively fewer electrochemically active
sites. These limitations can be effectively addressed through transition metal doping,
which improves conductivity and enhances electrochemical activity [2].
In the present work, Cr–Co co-doped MoS₂ was synthesized using a facile hydrothermal
method with varying dopant concentrations (1, 3, and 5 mol%) to enhance its
electrochemical performance. Additionally, the study demonstrates the use of a cost-
effective stainless-steel (SS) substrate, highlighting its potential for scalable and practical
applications. X-ray diffraction (XRD) and Raman spectroscopy confirmed successful
dopant incorporation, phase integrity, and lattice strain modification induced by Cr–Co
co-doping. The optimally doped MoS₂–3C electrode exhibited a high specific
capacitance of 678.24 F g⁻¹, nearly three times higher than pristine MoS₂ (222.84 F
g⁻¹). Furthermore, the energy density increased by approximately 51%, rising from
42.54 Wh kg⁻¹ for pristine MoS₂ to 64.21 Wh kg⁻¹ for MoS₂–3C. Electrochemical
impedance spectroscopy (EIS) revealed a significant reduction in both solution resistance
and charge transfer resistance to 4.82 Ω and 24.20 Ω, respectively, compared to 37.70 Ω
and 35.84 Ω for the undoped electrode. These findings demonstrate that rational Cr–Co
co-doping, combined with a low-cost SS substrate, effectively overcomes the intrinsic
limitations of MoS₂ and enhances its suitability for high-performance supercapacitor
applications.