Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, Genova 16146, Italia.
Istituto Italiano di Tecnologia, Nanobiointeractions & Nanodiagnostics, PVia Morego 30, Genova 16163, Italy.
Nano Lett. 2023 Apr 12;23(7):2644-2650. doi: 10.1021/acs.nanolett.2c04982. Epub 2023 Mar 30.
The growth of pyramidal platinum nanocrystals is studied by a combination of synthesis/characterization experiments and density functional theory calculations. It is shown that the growth of pyramidal shapes is due to a peculiar type of symmetry breaking, which is caused by the adsorption of hydrogen on the growing nanocrystals. Specifically, the growth of pyramidal shapes is attributed to the size-dependent adsorption energies of hydrogen atoms on {100} facets, whose growth is hindered only if they are sufficiently large. The crucial role of hydrogen adsorption is further confirmed by the absence of pyramidal nanocrystals in experiments where the reduction process does not involve hydrogen.
通过合成/表征实验和密度泛函理论计算的结合，研究了金字塔形铂纳米晶体的生长。结果表明，金字塔形状的生长是由于一种特殊类型的对称性破缺，这是由氢在生长的纳米晶体上的吸附引起的。具体来说，金字塔形状的生长归因于氢原子在{100}面上的尺寸相关吸附能，只有当它们足够大时，才会阻碍其生长。在不涉及氢的还原过程的实验中，不存在金字塔形纳米晶体，这进一步证实了氢吸附的关键作用。
