Interaction of a carbon atom on small platinum clusters and its effects on hydrogen binding

Ab initio calculations on interaction of a C atom on small Ptn clusters (n = 1-10) show strong carbidic bonding and a decrease in the magnetic moments of Pt clusters. The adsorption energy decreases in an oscillatory way with increasing size but suggests no graphitic phase on small Pt clusters. Ptn clusters (n < 7) remain nearly planar after C adsorption but larger clusters have 3D structure. Further calculations of infrared and Raman spectra are reported. Interaction of H on pure and PtnC clusters shows stronger binding of H on PtnC clusters suggesting their better reactivity.

Higher binding energy of an H atom on PtnC clusters compared with pure Ptn clusters.77Highlights► Strong carbidic interaction of a C atom on small Pt clusters. ► Transition from 2d to 3D structures of Ptn (n > 6) clusters with C interaction. ► With increasing n, sp to sp2 to sp3 and then mixed sp2-sp3 bonding of C in Ptn. ► Raman and infrared spectra supports bonding characteristics. ► H interacts more strongly on PtnC than on Ptn clusters.