Electrophoretic Deposition of MoS₂ Electrodes for Supercapacitor Applications
摘要
The synthesis of high-performance MoS₂ nanosheets for energy storage applications has traditionally relied on two main strategies: liquid-phase exfoliation of bulk MoS₂ or chemical intercalation using organolithium compounds. While the former yields semiconducting 2H-MoS₂ with limited conductivity and small flake sizes, the latter (organolithium intercalation) has historically been regarded as the most direct way to obtain metallic 1 T-MoS₂. This method is relevant because the 1 T phase exhibits much higher conductivity and enhanced electrochemical activity, making it particularly attractive for supercapacitor electrodes. However, despite these advantages, organolithium intercalation remains impractical for scalable production due to multi-day reaction times and the use of hazardous, air-sensitive reagents. More recently, an electrochemical route has been introduced as a more accessible method to synthesize metallic-phase MoS₂. In this approach, lithium ions from a lithium salt (LiClO₄) are electrochemically intercalated into MoS₂ using a platinum counter electrode, followed by rapid exfoliation upon exposure to water. This bench-top method produces high-quality 1 T-MoS₂ in under two hours, significantly lowering the barrier to producing conductive nanosheets for supercapacitor applications. Equally important is the choice of integration technique, which directly determines the electrochemical performance of the nanosheets. Literature reports show that conventional slurry-cast electrodes based on 1 T-MoS₂–graphene composites can deliver gravimetric capacitances above 70 F g⁻1 with excellent cycling stability. Notably, when the same composite materials were assembled using electrophoretic deposition (EPD), an additional performance enhancement of approximately 10% was observed. This key outcome underscores the potential of EPD to create uniform, binder-free, and densely packed electrode architectures, which translate into higher capacitance and long-term stability. These findings position EPD as a compelling and scalable integration strategy for high-performance energy storage devices.