Site-Specific Hydrogen Reactivity of Zn0.05Mg0.95O Nanopowders

Here we present a combined theoretical and experimental study of hydrogen adsorption on Zn-functionalized MgO surface. We have systematically compared infrared spectra recorded at increasing pressure (10–5–100 mbar) rock-salt Zn0.05Mg0.95O nanocubes. The interpretation vibrations involving was supported by ab initio calculations following the same strategy as for pure MgO. Despite small Zn concentration, unambiguously Zn-specific signals. Most interestingly, find that all chemisorption complexes, characteristic surface reactivity, remain highly preserved Zn0.05Mg0.95O, while effect segregated is strongly localized to its first oxygen neighbors. From intensity variation IR couples when passing from Zn-modified MgO, (1) confirm validity models previously proposed (2) show segregates preferentially low-coordination Mg sites (88% 50% substitution corners step edges, respectively). This demonstrates can serve specific probe low-coordinated ZnxMg1–xO due higher H– affinity Zn2+ than Mg2+ cations.