Highly Efficient Quasi-Solid-State Asymmetric Supercapacitors Based on MoS2/MWCNT and PANI/MWCNT Composite Electrodes

Abstract

Molybdenum disulfide (MoS 2 ) and polyaniline (PANI) electrodes were decorated with multi-walled carbon nanotubes (MWCNTs) on the basis of a facial hydrothermal and in situ polymerization methods and served in the asymmetric supercapacitor (ASC). The MoS 2 and MWCNTs with a mole ratio of 1:1 in MoS 2 |MWCNTs electrode exhibited better electrochemical properties through extensive electrochemical studies, in terms of the highest specific capacitance of 255.8 F/g at 1 A/g, low internal resistance, and notable electrochemical stability with retention of the initial specific capacitance at 91.6% after 1000 cycles. The as-prepared PANI|MWCNTs electrode also exhibited good specific capacitance of 267.5 F/g at 1 A/g and remained 97.9% capacitance retention after 1000 cycles. Then, the ASC with MoS 2 |MWCNTs and PANI|MWCNTs composite electrodes were assembled with polyvinyl alcohol (PVA)-Na 2 SO 4 gel electrolyte, which displayed good electrochemical performance with the specific capacitance of 138.1 F/g at 1 A/g, and remained the energy density of 15.09 Wh/kg at a high power density of 2217.95 W/kg. This result shows that this ASC device possesses excellent electrochemical properties of high energy density and power output and thus showing a potential application prospect.

MoWS2 nanosheets incorporated nanocarbons for high-energy-density pseudocapacitive negatrode material and hydrogen evolution reaction

“…where electrochemical potential m is rigidly shied by the e4. 40,41 The thermal broadening function F T (E) is expressed as (10):…”

“…7f). [4][5][6][7][8][9][10][11] The performance of an electrode with a higher mass loading was tested and can be found in the ESI Section; † we observed little change in the CV and GCD proles, but the capacitance and energy density values decreased due to the higher mass loading and thickness of the electrode (Fig. S6 †).…”

“…Overall, the HRTEM analysis validates the results obtained from XRD and FESEM, and the interaction and aggregation of the nanocarbons with MWS signies better electrochemical activity owing to their porous structure. 10,11,22,36 High-resolution XPS was employed to obtain a clear understanding of the binding energy and electronic state of the materials, as well as accurate atomic percentages. The survey spectrum provided in Fig.…”

“…have attracted profuse interest and attention due to their unique electrical, physicochemical, thermal, and optical properties. [10][11][12][13][14][15] Metal sulphides, owing to their tunable properties, defect-rich structure, superior conductivity, high pH tolerance, and diverse behaviour, have been particularly fruitful for attaining multifunctionality in the vast elds of supercapacitors, catalysis, batteries, solar cells, biomedical applications, etc. Molybdenum-and tungsten-based sulphides (MoS 2 and WS 2 ) are in demand among the metal sulphide family and have been widely investigated in the elds of supercapacitors and the HER due to their high catalytic activity and multiple oxidation variance.…”

“…Many undiscovered opportunities exist in this line of application and these materials can be tuned by several modication approaches as reported previously. [10][11][12] Recently, many research groups have been modifying the tunable properties of the aforementioned sulphides to obtain better results in energy conversion and energy storage applications. The incorporation of nanocarbons (single-walled and multi-walled carbon nanotubes (MWCNT), carbon nanober, graphene, nanodiamond, and reduced graphene oxide (rGO)) into the TMDCs not only provides high surface area and abundant active sites, but the nanocarbons also act as conductive skeletons for ion diffusion and transportation.…”