Unveiling the Effect of the Structure of Carbon Material on the Charge Storage Mechanism in MoS₂-Based Supercapacitors

Abstract

MoS 2 is a 2D material that has been widely used in supercapacitor applications because of its layered structure that provides a large surface area and allows for high electric double-layer charge storage. To enhance the cycling stability and capacitance of MoS 2 , it is usually mixed with carbon materials. However, the dependence of the charge storage mechanism on the structure of the carbon material is still unclear in literature. Herein, the effect of the structure of the carbon material on the charge storage mechanism in 2H flower-shaped MoS 2 is investigated in detail. Specifically, 2H MoS 2 was mixed with either 8 nm-diameter carbon nanotubes (CNTs) or graphene nanoflakes (GNFs) in different weight ratios. Also, a composite of MoS 2 , CNTs, and GNFs (1:1:1) was also studied. The charge storage mechanism was found to depend on the structure and content of the carbon material. Insights into the possible storage mechanism(s) were discussed. The MoS 2 /CNT/GNF composite showed a predominant pseudocapacitive charge storage mechanism where the diffusion current was ∼89%, with 88.31% of the resulted capacitance being due to faradic processes.

Revealing the role of the 1T phase on the adsorption of organic dyes on MoS2 nanosheets

“…Two-dimensional (2D) layered materials have attracted attention for a wide range of applications including hydrogen evolution, 1 adsorption, 2,3 photocatalysis, 4,5 lithium ion batteries, 6 and supercapacitors. [7][8][9] Among the different types of 2D materials, molybdenum disulde (MoS 2 ) has been one of the most studied materials over the last few years. 10,11 MoS 2 can exist in three phases; two are semiconducting and stable (hexagonal, 2H, and rhombohedral, 3R) and the third (1T) is metallic with a trigonal structure.…”

“…[1][2][3][4]6,7,12,20 However, several contradicting reports on this topic can be found due to the very delicate nature of the material. [1][2][3][4][6][7][8][9] The electronic structure of the material and its activity are quite sensitive to several parameters including the molybdenum local coordination, surface defects, crystal phase, degree of exfoliation, and the size and morphology of the nanosheets. For instance, several reports claimed fast and efficient adsorption of different organic dyes using MoS 2 composites.…”

Recycling of Li−Ni−Mn−Co Hydroxide from Spent Batteries to Produce High‐Performance Supercapacitors with Exceptional Stability

“…Figure c depicts the CCCD graphs at different current densities (1–4 A g −1 ), showing nonlinear curves of potential versus time, which confirm the battery‐like behavior of the recycled material . The specific capacitance of the recycled material was calculated from the CCCD graphs using Eq.…”

Recent advances in the use of TiO2 nanotube powder in biological, environmental, and energy applications

“…Second, materials that store energy through a fast-redox reaction from different chemical groups such as oxides, suldes, nitrides, or conducting polymers. 100,101 Third, composite materials of both active and double layer materials. 96,99 In battery-like materials, the capacitance is subject to change over the potential window.…”