Stabilizing Catalytically Active Nanoparticles by Ligand Linking: Toward Three-Dimensional Networks with High Catalytic Surface Area
Stabilizing Catalytically Active Nanoparticles by Ligand Linking: Toward Three-Dimensional Networks with High Catalytic Surface Area
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DOI：
10.1021/la4049055
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发表时间：
2014-05-20
期刊：
影响因子：
3.9
通讯作者：
Baeumer, Marcus
中科院分区：
文献类型：
--
作者：
Morsbach, Eva;Speder, Jozsef;Baeumer, Marcus
提出了一种用于将Pt纳米颗粒（NPs）与双官能胺配体（具有两个胺基的有机分子）连接的一般方法，该方法允许在没有无机载体和高密度的催化活性金属的情况下制备NP催化剂。利用了“未保护的”NP的使用，这使得我们能够从相同的颗粒批次制备不同的配体官能化的NP，从而将所得材料性质的变化专门与配体的影响相关联。三个双官能配体具有相似的官能团（胺），但不同的烃骨架，并与单官能配体的类似的分子结构（烷基和芳基胺），显示显着不同的材料性能进行了比较。具有较小空间需求的单官能分子几乎完全覆盖NP表面，并导致NP的二维组装。相比之下，使用双官能胺配体导致形成具有高密度的配体自由表面原子的多孔三维NP网络（配体连接的NP），从而使得能够作为催化材料应用。双功能配体的稳定作用作为使用无机载体材料的替代方案，并使配体连接的NP网络的催化应用成为可能。
A general approach for the linking of Pt nanoparticles (NPs) with bifunctional amine ligands (organic molecules with two amine groups) is presented that allows for the preparation of NP catalysts without inorganic supports and high densities of the catalytically active metal. Advantage was taken of the use of "unprotected" NPs, which enables us to prepare different ligand-functionalized NPs from the same particle batch and thus to relate changes of the resulting material properties exclusively to the influence of the ligand. Three bifunctional ligands with similar functional groups (amines) but different hydrocarbon skeletons were used and compared to monofunctional ligands of similar molecular structures (alkyl and aryl amines) showing significantly different material properties. Monofunctional molecules with minor steric demand cover almost completely the NP surface and lead to two-dimensional assembling of the NPs. In contrast, the use of bifunctional amine ligands leads to the formation of porous, three-dimensional NP networks (ligand-linked NPs) with a high density of ligand free surface atoms, thus enabling for the application as catalytic materials. The stabilizing effect of bifunctional ligands serves as an alternative to the use of inorganic support materials and enables for catalytic applications of ligand-linked NP networks.