Three-Dimensional Tubular MoS₂/PANI Hybrid Electrode for High Rate Performance Supercapacitor

Abstract

By using three-dimensional (3D) tubular molybdenum disulfide (MoS2) as both an active material in electrochemical reaction and a framework to provide more paths for insertion and extraction of ions, PANI nanowire arrays with a diameter of 10-20 nm can be controllably grown on both the external and internal surface of 3D tubular MoS2 by in situ oxidative polymerization of aniline monomers and 3D tubular MoS2/PANI hybrid materials with different amounts of PANI are prepared. A controllable growth of PANI nanowire arrays on the tubular MoS2 surface provides an opportunity to optimize the capacitive performance of the obtained electrodes. When the loading amount of PANI is 60%, the obtained MoS2/PANI-60 hybrid electrode not only shows a high specific capacitance of 552 F/g at a current density of 0.5 A/g, but also gives excellent rate capability of 82% from 0.5 to 30 A/g. The remarkable rate performance can be mainly attributed to the architecture with synergistic effect between 3D tubular MoS2 and PANI nanowire arrays. Moreover, the MoS2/PANI-60 based symmetric supercapacitor also exhibits the excellent rate performance and good cycling stability. The specific capacitance based on the total mass of the two electrodes is 124 F/g at a current density of 1 A/g and 79% of its initial capacitance is remained after 6000 cycles. The 3D tubular structure provides a good and favorable method for improving the capacitance retention of PANI electrode.

Polyaniline/MoSX Supercapacitor by Electrodeposition

“…In the CV curve of PANI, it shows a couple of conspicuous redox peaks at about +0.23 V and +0.09 V vs. Ag/AgCl, which apparently result from the conversion of PANI between a conducting state (emeraldine salt) and a semiconducting state (leucoemeraldine base). 13,15,43,44 It is of importance to mention that PANI/MoS X presents higher capacitance behaviors than individual PANI and MoS X . In addition, the CV curves of PANI/MoS X , PANI and one hand, with the increase of scan rate from 0.025 to 0.5 V s ¹1 , PANI CV curves show a positive shift of oxidative peaks and a slight negative shift of reductive peaks, which is mainly caused by electrode resistance.…”

“…44 On the other hand, PANI/MoS X and MoS X reveal weak peaks during the CV measurements, indicating the existence of pseudocapacitive behaviors. 13 Figure 4b shows the plots of current at a fixed potential of +0.4 V vs. scan rate. In order to calculate the specific capacitance from CV measurements, we used the following eq 1:…”

“…7,12 Currently, most of the research is focused on searching for composite electrode materials with superior electrochemical performance in order to satisfy future applications. Conducting polymer polyaniline (PANI) incorporated with transition metal dichalcogenides, 13,14 graphene oxide, 15 graphene, 16,17 carbon nanotube 18 and so on 19,20 have been reported to not only achieve higher capacitive performance, but also to solve the problem of poor cycle life of PANI. Among these composite electrode materials, the polymerization of aniline is triggered by chemical oxidation, 21 electrochemistry, 22 solution mixing, 23 self-assembly 24 and Pickering emulsion.…”

“…Three-dimensional tubular MoS 2 /PANI shows high rate performance for supercapacitors. 13 However, the polymerization of aniline to construct MoS 2 /PANI composite materials is accomplished only by chemical oxidation rather than electrochemistry.…”

Nanostructured MoS2/BiVO4 Composites for Energy Storage Applications

“…It should, however, be noted that over the last few years several studies that quantify the capacitive storage of MoS 2 have been reported111213141516171819202122; these typically use MoS 2 in conjunction with a variety of carbon allotropes, predominantly graphene (r-GO). Interestingly, as yet MoS 2 has not been coupled with a viable electrochemical component to form a hybrid supercapacitor.…”