Adsorption of H on Cs/W(110): Impact of H on the Stability of Cs on the Surface

Abstract

We studied the adsorption of H on Cs/W(110) by performing density functional theory (DFT) based total energy calculations to determine the influence of H on Cs stability on the surface. For reference, we also independently examined the adsorption of H and Cs on clean W(110). We found that the adsorption energies of both H and Cs decrease in the presence of the other. H adsorbs more strongly in H/W(110) as compared to the coadsorbed system H/Cs/W(110). We observe the same trend for Cs adsorption in Cs/W(110) and H/Cs/W(110) systems. Due to the greater electronegativity of H as compared to Cs, increasing the H coverage further weakens Cs adsorption on the W surface. The results suggest that the presence of H could lead to the desorption of Cs from the surface and thus, it is necessary to reevaluate the designs of Cs/W systems used in negative hydrogen production applications. [DOI: 10.1380/ejssnt.2018.391]