General Thermal Texturization Process of MoS₂ for Efficient Electrocatalytic Hydrogen Evolution Reaction

Abstract

Molybdenum disulfide (MoS2) has been widely examined as a catalyst containing no precious metals for the hydrogen evolution reaction (HER); however, these examinations have utilized synthesized MoS2 because the pristine MoS2 mineral is known to be a poor catalyst. The fundamental challenge with pristine MoS2 is the inert HER activity of the predominant (0001) basal surface plane. In order to achieve high HER performance with pristine MoS2, it is essential to activate the basal plane. Here, we report a general thermal process in which the basal plane is texturized to increase the density of HER-active edge sites. This texturization is achieved through a simple thermal annealing procedure in a hydrogen environment, removing sulfur from the MoS2 surface to form edge sites. As a result, the process generates high HER catalytic performance in pristine MoS2 across various morphologies such as the bulk mineral, films composed of micron-scale flakes, and even films of a commercially available spray of nanoflake MoS2. The lowest overpotential (η) observed for these samples was η = 170 mV to obtain 10 mA/cm(2) of HER current density.

On the impact of Vertical Alignment of MoS2 for Efficient Lithium Storage

“…S4). The A 1g to E g ratio is close to 1:2 ratio for the PO-MoS 2 25 while the VA-MoS 2 displays a 1:3 ratio revealing the edge terminated nature of the film, i.e. the vertical alignment 28 .…”

“…In particular, the majority of the extensive studies on MoS 2 growth strive to achieve continuous layers and heterostructures with PO suitable for electronic and optoelectronic devices 20–22 . Layered materials, MoS 2 in particular, have also been demonstrated as efficient and promising for energy storage applications 23–25 , where the weak interlayer force can accommodate intercalated ions very efficiently. However, for energy storage, the most efficient orientation of MoS 2 crystals is the vertical alignment (VA) to the substrate, and the desired thickness of the grown layer must be sufficient to insert as many ions as possible, intercalated between the MoS 2 crystal planes.…”

E’’ Raman Mode in Thermal Strain-Fractured CVD-MoS2

“…It is enhanced heavily by growing MoS2 thin films with vertically aligned layers in previous reports [17,18]. Recently, Our group reported the underlying formation mechanism of SF-MoS2 [19], where the number of edges increased heavily [14,20]. However, the structural and vibrational properties of such SF-MoS2 have not been investigated yet.…”

Nickel Hydr(oxy)oxide Nanoparticles on Metallic MoS2 Nanosheets: A Synergistic Electrocatalyst for Hydrogen Evolution Reaction

“…Extensive efforts have been made to improve the HER activities of MoS 2 ‐based catalysts in acidic media by strategies such as nanostructure engineering,35, 36, 37, 38 defect engineering,39, 40, 41, 42, 43 phase engineering,44, 45, 46, 47, 48 and heteroatom doping49, 50, 51 to increase the number or enhance the intrinsic activity of active sites. However, little work has been reported to improve the HER activities of MoS 2 ‐based materials in alkaline media 31, 52.…”