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Audiokassetten sind der Schlüssel zu einer verbesserten Fischer‐Tropsch‐Katalyse, denn schon im Zusammenhang mit deren Magnetbändern wurde die Herstellung von Partikeln aus billigen Eisenoxid‐Kernen mit sehr dünnen Cobalt‐Schalen (siehe Bild) optimiert. Diese Partikel sind ausgezeichnete Fischer‐Tropsch‐Katalysatoren für die Herstellung guter Diesel‐Fraktionen und leicht im großen Maßstab zugänglich.

In the last twenty years, remarkable advances in nanosciences and nanotechnology have given an impulse to the design of heterogeneous catalysts. Bell emphasized in 2003 the role of nanoparticle size in catalyst performance, [1] and Schlögl and Abd Hamid [2] proposed in 2004 that the synthesis of nanosized catalysts may require multidimensional structural control. Glow-discharge (luminous) plasma is obtained by applying a potential difference between two electrodes placed in a gas. The plasma provides energy for decomposition of metal precursors. Several active catalysts have been developed [3][4][5][6] by using glow discharge. The glow-discharge activation process is simple, quick, audio-visual, and easy to control. It does not require the high temperatures and significant amounts of compressed gases which are typically used in conventional catalyst pretreatments.The increasing interest in Fischer-Tropsch (FT) synthesis has been due to the growing demand for clean fuels and utilization of abundant natural gas, coal, and biomass-derived synthesis gas. [7,8] Cobalt catalysts are preferred for FT synthesis due to their high productivity, high selectivity for heavy hydrocarbons, high stability, and low activity in the water-gas shift reaction. [7,8] The catalytic performance of cobalt catalysts in FT synthesis appears to be strongly affected by the size of the cobalt metal particles. [7][8][9][10][11] Conventional cobalt FT catalysts are prepared by aqueous impregnation of supports (silica, alumina, titania, etc.) with solutions of cobalt salts. After decomposition of the supported cobalt salts by calcination in an oxidizing atmosphere, the catalysts are reduced in hydrogen to generate cobalt metal sites.The present work focuses on the effects of pretreatment with glow-discharge plasma on cobalt dispersion and reducibility in alumina-supported catalysts and their performance in FT synthesis. Details of catalyst preparation are given in the Experimental Section. Cobalt and platinum contents in catalysts were 15 wt % and 0

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Fine-tuned interaction between reacting molecules and metal surface is of great importance in heterogeneous catalysis for the design of highly selective processes. Conventional strategies based on adjusting the intrinsic catalyst properties such as particle size, metal-support interaction and morphology suffer from complicated and time-consuming synthetic procedures. Recently, the modification of metal nanoparticles with nonmetallic promoters has been demonstrated as an effective tool to regulate the interfacial environment of metallic catalysis. Herein, we will give an overview of recent progress in this area. A general analysis will be proposed about the electronic, steric effects and new functionalities imposed by nonmetallic promoters of metal catalysts. The potential for the selectivity enhancement of the promoted metal catalysts in various industrially important reactions is discussed.