Immobilization of cobalt porphyrin on CeO2@SiO2 core–shell nanoparticles as a novel catalyst for selective oxidation of diphenylmethane

In this study, CeO2@SiO2 core–shell nanoparticles have been synthesized and used as supports to graft cobalt porphyrin via an amide bond. The catalyst was characterized using techniques such as FT-IR, UV–vis, SEM, TEM and BET. The results show that the catalyst was composed of regular nanoparticles (around 50 nm) with a core–shell structure. In addition, the catalyst exhibits an excellent activity, selectivity and stability for solvent-free selective oxidation of diphenylmethane with atmospheric pressure of oxygen. The conversion of diphenylmethane was as high as 41.6% with selectivity to diphenyl ketone of 96.3%. Even after reused up to 6 times, the catalyst maintained stable working ability.

Graphical abstractCobalt tetraphenylporphyrin was immobilized onto CeO2@SiO2 nanoparticles via an amide bond. The catalyst exhibits an excellent catalytic activity, selectivity and stability for solvent-free highly selective oxidation of diphenylmethane by oxygen at ambient pressure.Figure optionsDownload full-size imageDownload high-quality image (93 K)Download as PowerPoint slideHighlights► CeO2 was modified by citrate sodium. ► CeO2@SiO2 core–shell nanoparticles have been synthesized. ► Metalloporphyrin was immobilized on CeO2@SiO2. ► The catalyst exhibits excellent catalytic performance for solvent-free oxidation of diphenylmethane to diphenyl ketone. ► The catalysts possess remarkable reusability.