Mechanistic insights into heterogeneous methane activation
| Autor: | Charlie Tsai, Allegra A. Latimer, Jong Suk Yoo, Max García-Melchor, Hassan Aljama, Jens K. Nørskov, Arvin Kakekhani, Frank Abild-Pedersen, Ambarish Kulkarni |
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| Rok vydání: | 2017 |
| Předmět: |
Range (particle radiation)
Chemistry business.industry Inorganic chemistry General Physics and Astronomy 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Methane 0104 chemical sciences Catalysis chemistry.chemical_compound Chemical physics Natural gas Yield (chemistry) Energy density Reactivity (chemistry) Physical and Theoretical Chemistry 0210 nano-technology business Scaling |
| Zdroj: | Physical Chemistry Chemical Physics. 19:3575-3581 |
| ISSN: | 1463-9084 1463-9076 |
| Popis: | While natural gas is an abundant chemical fuel, its low volumetric energy density has prompted a search for catalysts able to transform methane into more useful chemicals. This search has often been aided through the use of transition state (TS) scaling relationships, which estimate methane activation TS energies as a linear function of a more easily calculated descriptor, such as final state energy, thus avoiding tedious TS energy calculations. It has been shown that methane can be activated via a radical or surface-stabilized pathway, both of which possess a unique TS scaling relationship. Herein, we present a simple model to aid in the prediction of methane activation barriers on heterogeneous catalysts. Analogous to the universal radical TS scaling relationship introduced in a previous publication, we show that a universal TS scaling relationship that transcends catalysts classes also seems to exist for surface-stabilized methane activation if the relevant final state energy is used. We demonstrate that this scaling relationship holds for several reducible and irreducible oxides, promoted metals, and sulfides. By combining the universal scaling relationships for both radical and surface-stabilized methane activation pathways, we show that catalyst reactivity must be considered in addition to catalyst geometry to obtain an accurate estimation for the TS energy. This model can yield fast and accurate predictions of methane activation barriers on a wide range of catalysts, thus accelerating the discovery of more active catalysts for methane conversion. |
| Databáze: | OpenAIRE |
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