In heterogeneous catalysis, supports play a crucial role in modulating the geometric and electronic structure of the active metal phase for optimizing the catalytic performance. A γ-Al2O3 nanosheet that contains 27% pentacoordinate Al(3+) sites can nicely disperse and stabilize raft-like Pt-Sn clusters as a result of strong interactions between metal and support. Consequently, there are strong electronic interactions between the Pt and Sn atoms, resulting in an increase in the electron density of the Pt sites. When used in the propane dehydrogenation reaction, this catalyst displayed an excellent specific activity for propylene formation with >99% selectivity, and superior anti-coking and anti-sintering properties. Its exceptional ability to maintain the high activity and stability at ultrahigh space velocities further showed that the sheet construction of the catalyst facilitated the kinetic transfer process.

In heterogeneous catalysis,s upports play ac rucial role in modulating the geometric and electronic structure of the active metal phase for optimizing the catalytic performance.A g-Al 2 O 3 nanosheet that contains 27 %p entacoordinate Al 3+ sites can nicely disperse and stabilizeraft-like Pt-Sn clusters as ar esult of strong interactions between metal and support. Consequently,t here are strong electronic interactions between the Pt and Sn atoms,r esulting in an increase in the electron density of the Pt sites.When used in the propane dehydrogenation reaction, this catalyst displayed an excellent specific activity for propylene formation with > 99 %s electivity,a nd superior anti-coking and anti-sintering properties.I ts exceptional ability to maintain the high activity and stability at ultrahigh space velocities further showed that the sheet construction of the catalyst facilitated the kinetic transfer process.

Catalytic dehydrogenation of propane to propylene and by‐product hydrogen is an atom‐economical and environmentally friendly route. PtSn/Al2O3 catalysts have been industrialized in this process, but still suffer from platinum sintering and coke deposition under reaction conditions. Herein, we design a calcium‐modified PtSn/Al2O3 catalyst showing a superior propane dehydrogenation performance. The presence of calcium combined with unsaturated aluminum and tin could consist of a new local microenvironment that promotes the dispersion of the platinum species and increases the electron density of the platinum species, which improves the catalytic activity, facilitates propylene desorption and inhibits coke formation. As a result, the achieved PtSnCa/Al2O3 catalyst exhibits a higher propylene formation rate and a lower coke‐accumulation rate compared to the catalyst without Ca addition. Moreover, the size of active phase clusters (∼1 nm) remained almost unchanged after the catalytic test, indicating a superior sintering resistance.

Manganese oxide-doped Al2O3 microspheres were synthesized via a redox method, and were then deposited with Au nanoparticles using a deposition-precipitation method. The obtained catalyst is not only highly active and selective for the preferential oxidation of CO in a H2-rich stream, but also shows excellent stability in the co-presence of H2O and CO2 at 80 °C.

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