ABSTRACT

Two-dimensional molybdenum disulfide (MoS₂) nanosheets have emerged as a promising material for transparent, flexible micro-supercapacitors, but their use in electrodes is hindered by their poor electrical conductivity and cycling stability because of restacking. In this paper, we report a novel electrode architecture to exploit electrochemical activity of MoS₂ nanosheets. Electrochemically exfoliated MoS₂ dispersion was spin coated on mesh-like silver networks encapsulated with a flexible conducting film exhibiting a pseudocapacitive behavior. MoS₂ nanosheets were electrochemically active over the whole electrode surface and the conductive layer provided a pathway to transport electrons between the MoS₂ and the electrolyte. As the result, the composite electrode achieved a large areal capacitance (89.44 mF cm⁻² at 6 mA cm⁻²) and high energy and power densities (12.42 µWh cm⁻² and P = 6043 µW cm⁻² at 6 mA cm⁻²) in a symmetric cell configuration with 3 M KOH solution while exhibiting a high optical transmittance of ~80%. Because the system was stable against mechanical bending and charge/discharge cycles, a flexible micro-supercapacitor that can power electronics at different bending states was realized.

摘要

二维二硫化钼（MoS ₂）纳米片已成为一种有前景的透明、柔性微型超级电容器材料，但由于重新堆叠，其导电性和循环稳定性差，阻碍了它们在电极中的使用。在本文中，我们报告了一种新颖的电极结构，以利用MoS ₂纳米片的电化学活性。将电化学剥离的 MoS ₂分散体旋涂在网状银网络上，该网络用柔性导电膜封装，表现出赝电容行为。MoS ₂纳米片在整个电极表面上具有电化学活性，并且导电层提供了在MoS ₂和电解质之间传输电子的途径。结果，复合电极实现了大面积电容（6 mA cm ^-2时为 89.44 mF cm ^-2 ）和高能量和功率密度（6 mA cm -2时为 12.42 µWh cm ^-2和P = 6043 µW cm ^{-2 ） 2}）在具有 3 M KOH 溶液的对称池配置中，同时表现出约 80% 的高光学透射率。由于该系统在机械弯曲和充电/放电循环方面保持稳定，因此实现了一种可以在不同弯曲状态下为电子设备供电的柔性微型超级电容器。