Coordination polymer-derived non-precious metal catalyst for propane dehydrogenation: Highly dispersed zinc anchored on N-doped carbon

Abstract

Highly dispersed non-precious metal catalysts supported on carbon have been intensively explored in the field of heterogeneous catalysis and material science owing to its low price, special electronic and geometric structure. However, their application and improvement of catalytic efficiency in alkane dehydrogenation were chronically limited due to spontaneous aggregation of metal atoms under the harsh conditions, low loading content and the complex preparation process. A new type of lamellar coordination polymer and a series of well-dispersed zinc-based catalyst anchored on N-doped carbon nanosheets were prepared via a facile combination of self-assembly and controlled pyrolysis. These carbonized composites showed superior initial activity (the propane conversion at 34% and the olefin selectivity at 80%) and acceptable catalytic stability (the deactivation rate of 0.082 h−1) in propane DDH reactions (600 °C, 2.4 kPa C3H8, He balance). The structure analysis results indicated the zinc loading in the optimized sample can be up to 19 wt%, which was also effectively retained after reactions. The systematic investigation on structure–function relations revealed that the catalytic activity originated from highly dispersed Zn, and the improvement of its performance could be ascribed to the mutual promotion between zinc loading and specific surface area. This work provided new guidelines to enable further development of the carbon-supported zinc-based catalyst in alkane dehydrogenation reactions and promoted the rational design of highly dispersed metal materials.