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arXiv · 2010.10908

Substitutional VSn nanodispersed in MoS$_2$ film for Pt-scalable catalyst

Frederick Osei-Tutu Agyapong-Fordjour·Seok Joon Yun·Hyung-Jin Kim·Wooseon Choi·Soo Ho Choi·Laud Anim Adofo·Stephen Boandoh·Yong In Kim·Soo Min Kim·Young-Min Kim·Young Hee Lee·Young-Kyu Han·Ki Kang Kim
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Abstract

Among transition metal dichalcogenides (TMdCs) as alternatives for Pt-based catalysts, metallic-TMdCs catalysts have highly reactive basal-plane but are unstable. Meanwhile, chemically stable semiconducting-TMdCs show limiting catalytic activity due to their inactive basal-plane. Here, we propose metallic vanadium sulfide (VSn) nanodispersed in a semiconducting MoS2 film (V-MoS2) as an efficient catalyst. During synthesis, vanadium atoms are substituted into hexagonal monolayer MoS2 to form randomly distributed VSn units. The V-MoS2 film on a Cu electrode exhibits Pt-scalable catalytic performance; current density of 1000 mA cm-2 at 0.6 V, overpotential of -0.06 V at a current density of 10 mA cm-2 and exchange current density of 0.65 mA cm-2 at 0 V with excellent cycle stability for hydrogen-evolution-reaction (HER). The high intrinsic HER performance of V-MoS2 is explained by the efficient electron transfer from the Cu electrode to chalcogen vacancies near vanadium sites with optimal Gibbs free energy (-0.02 eV). This study adds insight into ways to engineer TMdCs at the atomic-level to boost intrinsic catalytic activity for hydrogen evolution.

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Frederick Osei-Tutu Agyapong-Fordjour, Seok Joon Yun, Hyung-Jin Kim, Wooseon Choi, Soo Ho Choi, Laud Anim Adofo, Stephen Boandoh, Yong In Kim, Soo Min Kim, Young-Min Kim, Young Hee Lee, Young-Kyu Han, Ki Kang Kim. 2020-10-21. Substitutional VSn nanodispersed in MoS$_2$ film for Pt-scalable catalyst. https://arxiv.org/abs/2010.10908

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