Organically Doped Metals-A New Approach to Metal Catalysis: Enhanced Ag-Catalyzed Oxidation of Methanol

We report here a new approach for the modification of the performance of metal catalysts: organic doping of the metal. Specifically, we report that the doping of Ag with Congo Red (CR@Ag) significantly improves the performance of Ag as a catalyst for methanol oxidation to formaldehyde, outperforming both pure Ag and CR‐coated Ag (CR/Ag) in terms of lowering the temperature needed for maximal conversion by 100 °C, lowering the temperature by 200 °C to reach the maximal selectivity (aldehyde formation), and increasing the maximal space velocity by a factor of two. We were led to this discovery by a detailed investigation of the thermal behavior (thermogravimetric and differential thermal analysis and mass spectroscopy) of CR@Ag under an oxidative atmosphere, which has indicated that the metal is strongly catalyzing the CR oxidation, and which pointed to the relevant temperature for activation of the catalyst. A new concept in catalytic materials is described: organically doped metals. Organically doped Ag greatly outperforms Ag as a catalyst for methanol oxidation to formaldehyde in terms of lowering the temperature needed for maximal conversion by 100 °C, and in lowering the temperature by 200 °C to reach the maximal selectivity (see figure).