Valcarcel Ana, Clotet Anna, Ricart Josep M, Delbecq Françoise, Sautet Philippe
Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel.lí Domingo s/n, E-43007 Tarragona, Spain.
J Phys Chem B. 2005 Jul 28;109(29):14175-82. doi: 10.1021/jp052087m.
The hydrogenation of 1,3-butadiene to different C4H8 species on both Pd(111) and Pt(111) surfaces has been studied by means of periodic slabs and DFT. We report the adsorption structures for the various mono- and dihydrogenated butadiene intermediates adsorbed on both metal surfaces. Radical species are more clearly stabilized on Pt than on Pd. The different pathways leading to these radicals have been investigated and compared to those producing 1-butene and 2-butene species. On palladium, the formation of butenes seems to be clearly favored, in agreement with the high selectivity to butenes observed experimentally. In contrast, the formation of dihydrogenated radical species seems to be competitive with that of butenes on platinum, which could explain its poorer selectivity to butenes and the formation of butane as a primary product.
通过周期性平板和密度泛函理论（DFT）研究了1,3 - 丁二烯在Pd(111)和Pt(111)表面氢化生成不同C4H8物种的过程。我们报告了各种单氢化和双氢化丁二烯中间体吸附在这两种金属表面的吸附结构。自由基物种在Pt上比在Pd上更稳定。已经研究了导致这些自由基的不同途径，并与生成1 - 丁烯和2 - 丁烯物种的途径进行了比较。在钯上，丁烯的形成似乎明显占优势，这与实验观察到的对丁烯的高选择性一致。相比之下，双氢化自由基物种的形成在铂上似乎与丁烯的形成相互竞争，这可以解释其对丁烯的选择性较差以及丁烷作为主要产物的形成。
