Electron-rich isolated Pt active sites in ultrafine PtFe3 intermetallic catalyst for efficient alkene hydrosilylation.

[Display omitted] • Ultrafine Pt-based intermetallic catalyst synthesized by in situ LRM strategy. • The electron-rich and isolated features of Pt sites in the Pt-based catalyst. • A superior catalytic performance for anti-Markovnikov alkene hydrosilylation. Regulating electronic structure of active centres to improve the performance of catalysts has always been a notable research topic, in which many challenges still need to be solved urgently. Herein, we report a PtFe 3 intermetallic catalyst anchored on N-doped carbon spheres (PtFe 3 /CN) with electron-rich isolated Pt active sites. The electron-rich nature of isolated Pt sites is attributed to the coordination of low electronegativity iron atoms. The PtFe 3 /CN catalyst showed a catalytic performance for the hydrosilylation of alkene superior to traditional single-atom Pt catalyst (coordinate with N etc. atoms) loading on N-doped graphene carbon (Pt1/CN) with electron-deficient isolated Pt sites and Pt nanoparticles supported N-doped carbon spheres (Pt NPs/CN) catalysts with the contiguous Pt sites. More importantly, turnover number (TON) of alkene hydrosilylation can reach a striking ca. 740,000 and no Pt leaching was detected. The opinion has been substantiated by both experimental and theoretical results that the PtFe 3 /CN catalyst can completely catalyze conversion of alkene and exhibit a high selectivity for anti-Markovnikov addition under environmentally friendly and mild conditions. [ABSTRACT FROM AUTHOR]