Evaluating the Effect of Varying the Metal Precursor in the Colloidal Synthesis of MoSe2 Nanomaterials and Their Application as Electrodes in the Hydrogen Evolution Reaction

Abstract

Herein we report on the use of different metal precursors in the synthesis of MoSe2 nanomaterials in order to control their morphology. The use of Mo(CO)6 as the metal precursor resulted in the formation of wrinkled few-layer nanosheets, while the use of H2MoO4 as the metal precursor resulted in the formation of nanoflowers. To investigate the effect of the morphologies on their performance as catalysts in the hydrogen evolution reaction, electrochemical characterization was done using linear sweep voltammetry (LSV), cyclic voltammetry (CV), and electrical impedance spectroscopy (EIS). The MoSe2 nanoflowers were found to have superior electrochemical performance towards the hydrogen evolution reaction with a lower Tafel slope, on-set potential, and overpotential at 10 mA/cm2 compared to the wrinkled few-layer nanosheets. This was found to be due to the higher effective electrochemical surface area of the nanoflowers compared to the nanosheets which suggests a higher number of exposed edge sites in the nanoflowers.

Colloidal Synthesis of Zirconium Disulphide Nanostructures and their Stability Against Oxidation

“…Colloidal synthesis of other 2D nanomaterials is relatively simpler. The Moloto group has fabricated several 2D nanomaterials including InSe, In 2 S 3 , AuSe, MoSe 2 and WS 2 among many others using the colloidal method of synthesis [17–21] . This method also provided the Moloto group an avenue to fabricate hierarchical nanostructures in the form of nanoflowers of MoSe 2, NbSe 2 and WS 2 by varying the reaction parameters.…”

Exfoliation methods for compositional and electronic characterization of interfacial Mo(Sex,Sy) in Cu(In,Ga)(Se,S)2 solar cells by X‐ray and UV photoelectron spectroscopy

“…For instance, MoSe 2 is treated as a promising material for energy storage, catalysis, and optoelectronics 5 . The application of MoSe 2 nanostructures grown by a wet‐chemical approach as catalyst for the hydrogen evolution reaction (HER) in electrochemical water splitting was investigated recently 6 . Thin films of MoSe 2 or MoS 2 can also be synthesized by electrochemical atomic layer deposition (E‐ALD), 7 chemical vapor deposition (CVD), 8 or simply by heating Mo foils under chalcogen atmosphere 9 .…”

Colloidal Control of Branching in Metal Chalcogenide Semiconductor Nanostructures

“…Metal and chalcogenide precursors have been shown to moderate branching in NCs due to their molecular composition or reactivity. 30 In the case of metal precursors, metal acetates have been shown to induce branching during the colloidal synthesis of various metal chalcogenides. One such observation was made during the synthesis of In 2 S 3 by Horani et al 24 Figure 1 presents a schematic illustration of In 2 S 3 branched nanostructures observed due to the type of indium precursor used during the hot-injection synthesis of In 2 S 3 in Horani et al 24 When In(Ac) 3 was used as the In precursor, the growing In 2 S 3 nanodots underwent a series of morphological evolution and assembly before finally attaining the nanosheet morphology.…”

“…As mentioned above, during the colloidal synthesis of nanocrystals (as in any reaction), the type of precursor molecules, precursor reactivity, ligands, solvents, and temperature play crucial roles in shaping the course of the reaction and NC morphology. Metal and chalcogenide precursors have been shown to moderate branching in NCs due to their molecular composition or reactivity . In the case of metal precursors, metal acetates have been shown to induce branching during the colloidal synthesis of various metal chalcogenides.…”