Colloidal synthesis of metal nanocrystals (NC) offers control over size, crystal structure and shape of nanoparticles, making it a promising method to synthesize model catalysts to investigate structure-performance relationships. Here, we investigated the synthesis of disk-shaped Co-NC, their deposition on a support and performance in the Fischer–Tropsch (FT) synthesis under industrially relevant conditions. From the NC synthesis, either spheres only or a mixture of disk-shaped and spherical Co-NC was obtained. The disks had an average diameter of 15 nm, a thickness of 4 nm and consisted of hcp Co exposing (0001) on the base planes. The spheres were 11 nm on average and consisted of ε-Co. After mild oxidation, the CoO-NC were deposited on SiO₂ with numerically 66% of the NC being disk-shaped. After reduction, the catalyst with spherical plus disk-shaped Co-NC had 50% lower intrinsic activity for FT synthesis (20 bar, 220 °C, H₂/CO = 2 v/v) than the catalyst with spherical NC only, while C₅₊-selectivity was similar. Surprisingly, the Co-NC morphology was unchanged after catalysis. Using XPS it was established that nitrogen-containing ligands were largely removed and in situ XRD revealed that both catalysts consisted of 65% hcp Co and 21 or 32% fcc Co during FT. Furthermore, 3–5 nm polycrystalline domains were observed. Through exclusion of several phenomena, we tentatively conclude that the high fraction of (0001) facets in disk-shaped Co-NC decrease FT activity and, although very challenging to pursue, that metal nanoparticle shape effects can be studied at industrially relevant conditions.

金属纳米晶体（NC）的胶体合成可控制纳米颗粒的大小，晶体结构和形状，这使其成为合成模型催化剂以研究结构与性能之间关系的有前途的方法。在这里，我们研究了圆盘形Co-NC的合成，它们在支撑体上的沉积以及费托合成（FT）在工业相关条件下的合成性能。从NC合成中，仅获得球体，或者获得圆盘状和球形Co-NC的混合物。圆盘的平均直径为15 nm，厚度为4 nm，由在基面上暴露的hcp Co（0001）组成。球体平均为11 nm，由ε- Co组成。温和氧化后，CoO-NC沉积在SiO _2上其中数控的66％为盘状。还原后，具有球形加盘状Co-NC的催化剂与仅具有球形NC的催化剂相比，FT合成（20 bar，220°C，H ₂ / CO = 2 v / v）的固有活性低50％，而C ₅₊选择性相似。令人惊讶的是，催化后Co-NC形态没有变化。使用XPS可以确定，大部分的含氮配体已被去除，原位XRD显示两种催化剂在FT期间均由65％hcp Co和21或32％fcc Co组成。此外，观察到3–5 nm的多晶域。通过排除几种现象，我们初步得出结论：圆盘形Co-NC中高比例的（0001）刻面会降低FT活性，并且尽管追求极具挑战性，但可以在工业上相关的条件下研究金属纳米颗粒形状的影响。