Bulk Fabrication of WS₂ Nanoplates: Investigation on the Morphology Evolution and Electrochemical Performance

Abstract

Two-dimensional layered chalcogenide WS2, similar to graphene, is considered to be very interesting for materials scientists. However, to make it a useful material platform, it is necessary to develop sophisticated synthesis methods to control its morphology. In this paper, we present a simple approach to prepare various morphologies of WS2 nanostructures by direct thermal evaporation of WO3 and S powders onto Si substrates sputtered with W film without using any nanostructured W-contained precursors and highly toxic sulfide gases. This method can produce bulk quantities of pure hexagonal, horizontally grown WS2 nanoplates, vertically grown nanoplates, and nanoplate-formed flowers simply by tuning the distance between the substrate and source powders. The synthesis mechanism and morphology evolution model were proposed. Moreover, when employed as a thin-film anode material, the Li-ion battery with as-prepared, vertically grown WS2 nanoplates presented a rechargeable performance between 3 and 0.01 V with a discharge capacity of about 773 mAh/cm(3) after recycling three times, much better than its already-reported counterparts with randomly distributed WS2 nanosheet electrodes, but the battery with horizontally grown WS2 nanoplates could not show any charge-discharge cycling property, which could be attributed to the different structures of WS2 anodes for Li(+) ion intercalation or deintercalation.

Tungsten disulfide: synthesis and applications in electrochemical energy storage and conversion

“…Their results manifested the electrochemical insertion of Li + into 3R-WS 2 was observed in two different regimes with a transition at about x = 0.2 (Li x WS 2 ), and moreover, they verified the high [146]. Since then, a few attempts were made to investigate the lithium storage activities of WS 2 [24,[147][148][149][150]. A case in point is the use of WS 2 nanotube (synthesized under high-temperature treatment in the presence of H 2 using amorphous WS 3 as raw material) as an anode for LIBs by Wang et al [24] in 2004, and the as-obtained WS 2 nanotube showed a good cycling stability in the wide potential range of 0.…”

Growth and Mechanism of MoS2Nanoflowers with Ultrathin Nanosheets

“…The as-proposed vertically grown MoS 2 nanoflowers with ultrathin nanosheets were prepared by CVD in a horizontal quartz tube furnace with two temperature zones working with different heating resistors [30]. By making use of this equipment, we can effectively and accurately control the temperature gradient of the furnace along the quartz tube.…”

WS2 and MoS2 counter electrode materials for dye‐sensitized solar cells

“…Along with other TMDs, tungsten dichalcogenides have been examined as a potential candidate in lithium‐ion batteries (LIBs) to be used as anode 60–63 . Battery performance would be improved when the electrochemical of the diffusion channels in the 2D layers of TMDs is accessible.…”

“…Battery performance would be improved when the electrochemical of the diffusion channels in the 2D layers of TMDs is accessible. It has been proved that WS 2 nanosheets exhibit a considerable battery performance when they are deposited vertically on the substrate surface of electrode than horizontally 61 . However, a conductive agent would be required because the electrical conductivity of the particles is not sufficient enough and the cyclability is poor 64,65 .…”

“…Along with other TMDs, tungsten dichalcogenides have been examined as a potential candidate in lithium-ion batteries (LIBs) to be used as anode. [60][61][62][63] Battery performance would be improved when the electrochemical of the diffusion channels in the 2D layers of TMDs is accessible. It has been proved that WS 2 nanosheets exhibit a considerable battery performance when they are deposited vertically on the substrate surface of electrode than horizontally.…”