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arXiv · 2502.11781

Quantum Tunneling Enhanced Hydrogen Desorption from Graphene Surface: Atomic versus Molecular Mechanism

Yangwu Tong·Yong Yang
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Abstract

We study the desorption mechanism of hydrogen isotopes from graphene surface using first-principles calculations, with focus on the effects of quantum tunneling. At low temperatures, quantum tunneling plays a dominant role in the desorption process of both hydrogen monomers and dimers. In the case of dimer desorption, two types of mechanisms, namely the traditional one-step desorption in the form of molecules (molecular mechanism), and the two-step desorption in the form of individual atoms (atomic mechanism) are studied and compared. For the ortho-dimers, the dominant desorption mechanism is found to switch from the molecular mechanism to the atomic mechanism above a critical temperature, which is respectively ~ 300 K and 200 K for H and D.

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Yangwu Tong, Yong Yang. 2025-02-17. Quantum Tunneling Enhanced Hydrogen Desorption from Graphene Surface: Atomic versus Molecular Mechanism. https://doi.org/10.1088/0256-307x%2F41%2F8%2F086801

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