Colloidal chemistry is very efficient in providing nanocrystals of well‐controlled structural characteristics. Although nanoparticles are essential components of heterogeneous catalysts, colloidal methods are rarely employed for their preparation. We have employed a seed‐mediated growth approach for modifying the structural characteristics of a conventional cobalt‐based Fischer–Tropsch catalyst. The Co particles of this catalyst can play the role of seeds for the overgrowth of shape‐ and structure‐controlled cobalt nanostructures by using a simple wet chemical method involving a molecular cobalt precursor and stabilizing agents. Thus, cobalt nanorods exhibiting the hexagonal compact structure were selectively grown on the immobilized Co particles of a reference Co/Al₂O₃–SiO₂ catalyst. The as‐obtained catalyst shows a better stability than a reference catalyst for the Fischer–Tropsch reaction. The removal of most of the ligands from the nanorod catalyst allows the catalyst activity to be improved while maintaining its stability. This is a proof of concept concerning the implementation of wet chemistry nanoparticle synthesis for the modification of heterogeneous catalysts.

中文翻译：

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种子介导的改性多相催化剂的制备方法

胶体化学在提供具有良好控制的结构特征的纳米晶体方面非常有效。尽管纳米颗粒是非均相催化剂的基本组成部分，但胶体方法很少用于制备。我们采用了一种种子介导的生长方法来改变常规钴基费-托催化剂的结构特征。通过使用涉及分子钴前体和稳定剂的简单湿化学方法，该催化剂的Co颗粒可充当种子，用于形状和结构受控的钴纳米结构的过度生长。因此，在固定的参比Co / Al ₂ O ₃ -SiO的Co颗粒上选择性地生长出具有六角形致密结构的钴纳米棒。₂催化剂。对于费-托反应，所获得的催化剂显示出比参比催化剂更好的稳定性。从纳米棒催化剂中除去大多数配体使得催化剂活性得以改善，同时保持其稳定性。这是关于湿化学纳米颗粒合成的实施以改性非均相催化剂的概念的证明。