Facile Synthesis of Molybdenum Diselenide Layers for High-Performance Hydrogen Evolution Electrocatalysts

Abstract

A cost-effective solution-based synthesis route to grow MoSe 2 thin films with vertically aligned atomic layers, thereby maximally exposing the edge sites on the film surface as well as enhancing charge transport to the electrode, is demonstrated for hydrogen evolution reaction. The surface morphologies of thin films are investigated by scanning electron microscopy and atomic force microscopy, and transmission electron microscopy analyses confirm the formation of the vertically aligned layered structure of MoSe 2 in those films, with supporting evidences obtained by Raman. Additionally, their optical and compositional properties are investigated by photoluminescence and X-ray photoelectron spectroscopy, and their electrical properties are evaluated using bottom-gate field-effect transistors. The resultant pristine MoSe 2 thin film exhibited low overpotential of 88 mV (at 10 mA·cm –2 ) and a noticeably high exchange current density of 0.845 mA·cm –2 with excellent stability, which is superior to most of other reported MoS 2 or MoSe 2 -based catalysts, even without any other strategies such as doping, phase transformation, and integration with other materials.

Design of Basal Plane Edges in Metal-Doped Nanostripes-Structured MoSe2 Atomic Layers To Enhance Hydrogen Evolution Reaction Activity

“…The solution bath technique was used to prepare metal-doped MoSe 2 atomic layers. , All the source chemicals such as selenium dioxide (SeO 2 ), ammonium molybdate ((NH 4 ) 6 Mo 7 O 24 ), manganese chloride (MnCl 2 ), ferrous chloride (FeCl 2 ), and cupric chloride (CuCl 2 ) were purchased from Sigma-Aldrich, Korea. SiO 2 (300 nm)/Si and Si substrates were purchased from Silicon Technology Corp, Japan.…”

“…FFT patterns and phase profile spectra were observed with the support of a Gatan DigitalMicrograph version 3.21. The TEM sample was prepared by following the reported procedure . X-ray photoelectron spectroscopy (XPS) analysis was performed using a PHI 5000 Versa probe (25 WAl Kα, 6.7 × 10 –8 Pa).…”

“…In particular, MoSe 2 , an inorganic TMDC with an analogous structure to MoS 2 , has been widely studied in the context of worldwide concern to move from fossil fuels due to its convenient band gap. ,− MoSe 2 has high electrical conductivity due to Se’s partial metallic nature, , and its edge site surface energy is greater than for the terrace sites, similar to other TMDCs, providing more basal planes as terminating surfaces. Thus, Mo and Se edges in the MoSe 2 atomic layers are highly active for electrochemical HER .…”

Fabrication of Robust Hydrogen Evolution Reaction Electrocatalyst Using Ag2Se by Vacuum Evaporation

“…HER kinetics can be processed via a Volmer-reaction (discharge step, Equation (1)) tailed by either an Heyrovsky reaction (ion-atom step, Equation (2)), or combination process (Tafel-reaction, Equation (3)) [33,34].…”

WS(1−x)Sex Nanoparticles Decorated Three-Dimensional Graphene on Nickel Foam: A Robust and Highly Efficient Electrocatalyst for the Hydrogen Evolution Reaction

“…The development of an inexpensive, Earth-abundant, highly active, and acid-stable material to use as an electrocatalyst is a grand challenge. In recent years, tremendous effort has been made to develop efficient HER catalysts from Earth-abundant materials with lots of active edges to replace Pt, such as transition-metal-based oxides/hydroxides, non-oxides, including metal based sulfides [ 4 , 5 , 6 ], selenides [ 7 , 8 , 9 ], carbides [ 10 , 11 ], phosphides [ 12 , 13 ], borate [ 14 ], phosphate [ 15 ], and their alloys. However, so far most of the catalysts exhibit inferior efficiency compared to Pt, while many processes involve complicated material synthesis and multiple steps, which may result in the increase of cost and further limit potential applications.…”