Brooks Alastair, Jenkins Stephen J, Wrabetz Sabine, McGregor James, Sacchi Marco
Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Abteilung Anorganische Chemie, c/o IRIS Adlershof, Zum Großen Windkanal 2, 12489 Berlin, Germany.
J Colloid Interface Sci. 2022 Aug;619:377-387. doi: 10.1016/j.jcis.2022.03.128. Epub 2022 Mar 31.
The dehydrogenation of alkane feedstock to produce alkenes is a significant and energy intensive industrial process, generally occurring on metals and metal oxides. Here, we investigate a catalytic mechanism for the dehydrogenation of butane on single-layer, metal-free graphene using a combination of ab initio quantum chemical calculations and adsorption microcalorimetry. Dispersion-corrected Density Functional Theory (DFT) is employed to calculate transition states and energy minima that describe the reaction pathways connecting butane to the two possible products, but-1-ene and but-2-ene. The deprotonations occur with moderate energy barriers in the 0.54 eV-0.69 eV range. A strong agreement is observed between the results of the adsorption energies calculated by DFT (0.40 eV) and the measured differential heat of adsorption of n-butane on a graphitic overlayer. We conclude that the active-site for this catalytic reaction is a metal-free graphene vacancy, created by removing a carbon atom from a single-layer graphene sheet.
将烷烃原料脱氢以生产烯烃是一个重要且能源密集型的工业过程，通常发生在金属和金属氧化物上。在此，我们结合从头算量子化学计算和吸附量热法，研究了单层无金属石墨烯上丁烷脱氢的催化机制。采用色散校正密度泛函理论（DFT）计算过渡态和能量最小值，这些描述了将丁烷连接到两种可能产物1-丁烯和2-丁烯的反应途径。去质子化过程的能垒适中，在0.54 eV - 0.69 eV范围内。通过DFT计算得到的吸附能（0.40 eV）与在石墨覆盖层上测量的正丁烷吸附微分热结果之间观察到了很强的一致性。我们得出结论，该催化反应的活性位点是通过从单层石墨烯片上去除一个碳原子而产生的无金属石墨烯空位。
