Mild Liquid-Phase Exfoliation of Transition Metal Dichalcogenide Nanosheets for Hydrogen Evolution

Abstract

Developing a general strategy to efficiently exfoliate transition metal dichalcogenide (TMD) electrocatalysts would be significantly beneficial for the electrocatalytic hydrogen evolution reaction (HER) from water splitting. However, there are several challenges in the production of two-dimensional (2D) TMDs, including the complicated fabrication process, high defect rate, and low production yield. Herein, we developed a general applicable mild organic molecular intercalator-assisted liquid-phase exfoliation method to produce TMD nanosheets in a large scale. The as-prepared ultrathin WSe2, MoSe2, WS2, and MoS2 nanosheets have a 2D nanosheet structure with a thickness of ∼3 nm and lateral size in a few hundred nanometers. This mild intercalation method can avoid introducing harsh exfoliation conditions used in conventional liquid-phase exfoliation, electrochemistry exfoliation, and lithium intercalation, thus resulting in high-quality exfoliation of TMD crystals. Additionally, benefiting from superior intrinsic electrical conductivity, unique 2D structure, and highly exposed active sites, the exfoliated WSe2 and MoSe2 nanosheets exhibited excellent catalytic activity for HER in acid with overpotentials of 223 and 225 mV at a current density of 10 mA cm–2 and low Tafel slopes of 64 and 65 mV dec–1, respectively.

Progress and development on the synthesis and application of two-dimensional molybdenum disulphide

“…In LPE approach, the bulk MoS 2 is inserted in an aqueous surfactant solution followed by sonication to separate the atomic layers. 136,137 This technique is used for the synthesis of large quantities and high quality 2D MoS 2 . LPE has good electrochemical and electron transfer ability; because of this the MoS 2 films grown by this method are mostly preferred for electrochemical storage, catalysis and sensing applications.…”

Recent advances in two-dimensional p-type metal chalcogenides: synthesis, doping strategies and applications

“…Intercalation LPE is another representative top-down way for the production of 2D p-type MCs [63,[66][67][68]. The basic strategy of this method is to intercalate molecules such as ions or organic molecules into layered bulk crystals, which could expand the interlayer distance of bulk material and waken the vdW interaction between layers [45].…”

“…Ambrosi et al successfully exfoliated 2D WSe 2 by using tert-butyllithium as an intercalant [67]. In addition, some organic molecules are also explored for the mild exfoliation of 2D p-type MCs [66]. Zhang et al reported the exfoliation of WSe 2 via mild intercalation LPE [66].…”

“…In addition, some organic molecules are also explored for the mild exfoliation of 2D p-type MCs [66]. Zhang et al reported the exfoliation of WSe 2 via mild intercalation LPE [66]. Dodecyl trimethylammonium chloride is used as the intercalant to assist the exfoliation of bulk WSe 2 , MoSe 2 , WS 2, and MoS 2 .…”

Simulation Photosynthesis Improves the Photoresponse Performance of Cr2Ge2Te6 Nanosheets for High-Performance Self-Powered Photoelectrochemical Photodetectors

“…The device exhibited good photoresponse performance and bending−folding stability and has great application potential in the field of flexible optoelectronic devices. 22,23 The bulk Gr 2 Ge 2 Te 6 crystals were added to the triturator and milled for 30 min to make the bulk crystals into powder. In quick succession, the collected Gr 2 Ge 2 Te 6 crystal powders were uniformly dispersed into N-methylpyrrolidone (NMP) solution, in which NMP served as a dispersant and acted as a barrier to air and moisture.…”