Surfactant‐Assisted Stabilization of Au Colloids on Solids for Heterogeneous Catalysis

The stabilization of surfactant‐assisted synthesized colloidal noble metal nanoparticles (NPs, such as Au NPs) on solids is a promising strategy for preparing supported nanocatalysts for heterogeneous catalysis because of their uniform particle sizes, controllable shapes, and tunable compositions. However, surfactant removal to obtain clean surfaces for catalysis through traditional approaches (such as solvent extraction and thermal decomposition) can easily induce the sintering of NPs, greatly hampering their use in synthesis of novel catalysts. Such unwanted surfactants have now been utilized to stabilize NPs on solids by a simple yet efficient thermal annealing strategy. After being annealed in N₂ flow, the surface‐bound surfactants are carbonized in situ as sacrificial architectures that form a conformal coating on NPs and assist in creating an enhanced metal‐support interaction between NPs and substrate, thus slowing down the Ostwald ripening process during post‐oxidative calcination to remove surface covers.     

Der lange Weg zum Makromolekül

At about 1920 Hermann Staudinger coined the term macromolecule. It is based on Berzelius' term polymeric and has a long history, including Grahams' colloids and Naegelis micelles. Finally, in the 1930 the theses of Staudinger on size and structure of macromolecules were generally accepted and macromolecular chemistry is since that time the basis of the industry of plastics and rubber.