A first-principles study on the hydrogen evolution reaction of VS₂ nanoribbons

Abstract

Nanostructures have attracted increasing interest for applications in electrolysis of water as electrocatalysts. In this work, the edge-catalytic effects of one dimensional (1D) VS2 nanoribbons with various edge configurations and widths have been investigated based on first-principles calculations. We show that the catalytic ability of VS2 nanoribbons strongly depends on their edge structure, edge configuration, and width. We find that the S-edges of VS2 nanoribbons are more active in electrolysis of water than V-edges due to their optimal Gibbs free energy for hydrogen evolution reaction in a wider range of hydrogen coverages. We also find that narrow nanoribbons show better catalytic performance than their wide counterparts. We further show that the S-edge of narrow VS2 nanoribbons with their V-edge covered by eight sulfur atoms has near-zero Gibbs free energy of hydrogen adsorption and comparable catalytic performance with Pt to a wide range of hydrogen coverage, which is contributed to its metallic characteristic. We expect that VS2 nanoribbons would be a promising 1D catalyst in electrolysis of water because of their impressive catalytic abilities both on the basal planes and edges.

Ultra-high electrochemical catalytic activity of MXenes

“…Importantly, both differential and average Gibbs free energies of W 2 C-TM and W 2 CH-TM are within a range of −0.2 to 0.1 eV in the whole H-coverage (n = 1~4) (Figs 3e,f and 4e,f), indicating its excellent performance in hydrogen evolution reaction. Their HER activities are much better than MX 2 monolayers and nanoribbons when considering the H-coverage density and oeverpotentials, where 2D MX 2 only showed high activities at certain H-density2326293031323334355455 (Supporting data, Table S-2). A recent work on V 2 CO 2 was noticed during revision, which showed that pure monolayer is worse on HER, while metal-decoration on its surface could improve its HER performance at certain H-coverage56.…”

“…Extensive efforts have been carried out to reduce the amounts of noble metals by alloying with cheap metals and tuning the composition of the catalysts789101112. Alternatively, novel electrocatalysts with low cost and rich abundance have been widely investigated to replace noble-metal catalysts1314151617181920212223242526272829303132333435. Especially, two-dimensional (2D) monolayers as electrocatalysts, such as 2D transition-metal dichalcogenides monolayers (TMDs), have been attracting increasing interests because of their unique physical and chemical properties20212223242526272829303132333435.…”

“…Alternatively, novel electrocatalysts with low cost and rich abundance have been widely investigated to replace noble-metal catalysts1314151617181920212223242526272829303132333435. Especially, two-dimensional (2D) monolayers as electrocatalysts, such as 2D transition-metal dichalcogenides monolayers (TMDs), have been attracting increasing interests because of their unique physical and chemical properties20212223242526272829303132333435. Experimental and theoretical studies showed that the electrocatalytic activity strongly depended on their structure, conductivity, edge states, defects, tensile strain, etc20212223242526272829303132333435.…”

“…Especially, two-dimensional (2D) monolayers as electrocatalysts, such as 2D transition-metal dichalcogenides monolayers (TMDs), have been attracting increasing interests because of their unique physical and chemical properties20212223242526272829303132333435. Experimental and theoretical studies showed that the electrocatalytic activity strongly depended on their structure, conductivity, edge states, defects, tensile strain, etc20212223242526272829303132333435. For example, the electrocatalytic activities of semiconducting TMDs in electrolysis of water were contributed to their metallic edges2529.…”

One-pot synthesis of nanosheet-assembled hierarchical MoSe2/CoSe2 microcages for the enhanced performance of electrocatalytic hydrogen evolution

“…[38][39][40][41][42] Both experimental and theoretical studies have conrmed that the HER activity of electrocatalysts correlates with the number of catalytically active edge sites. [43][44][45][46][47][48][49][50][51] It has also proved that the edges of the TMD sheets play an important role in HER process. The edges have a large presence of unsaturated bonds and therefore unpaired electrons, whereas the basal surfaces of the sheets are catalytically inert.…”