A hollow in hollow nanoreactor of H-PtCu@SiO2 for the selective transfer hydrogenation

Hollow metal nanoparticles have attracted great interest in heterogeneous catalysis research due to their unique structures as nanoreactors. Here, we report hollow PtCu nanoparticles encapsulated in microporous silica shells (H-PtCu@SiO2), which can serve as the nanoreactor with high catalytic activity and high stability. The H-PtCu@SiO2 nanoreactor shows the state-of-the-art catalytic performance for the transfer hydrogenation of benzonitrile to dibenzylamine, which achieves up to 100% conversion and 99% selectivity in only 0.5 h. The void-confinement effect of H-PtCu@SiO2 is crucial for the outstanding catalytic performance by encaging the reactants in the nanoreactor. The computation demonstrates the limiting diffusion effect of the silica shell toward the ammonia borane, thus reduces the concentration of reductant species and prolongs the lifetime of the intermediate imine to improve the selectivity of secondary amine. Moreover, the silica shells can effectively enhance the catalytic stability of the H-PtCu@SiO2 nanoreactor.

Automated summary

The hollow PtCu nanoparticles encapsulated in microporous silica shells serve as high-performance nanoreactors in catalysis, achieving excellent conversion and selectivity for the transfer hydrogenation reaction. The silica shell plays a crucial role in limiting diffusion, reducing reductant concentration, and improving selectivity of the reaction, while also enhancing the catalytic stability of the nanoreactor.