image: CeO2-supported bi-layer Pt clusters enable efficient stable anti-Markovnikov alkene hydrosilylation
Credit: ©Science China Press
A research team led by Professor Jie Zeng and Associate Researcher Han Yan from the University of Science and Technology of China, in collaboration with Professor Chao Ma of Hunan University, has developed a breakthrough platinum bilayer cluster catalyst addressing critical industrial challenges in alkene hydrosilylation—a pivotal process for organosilicon production. While industry has long relied on homogeneous platinum catalysts plagued by high metal consumption, low product purity from side reactions, and metallic residue contamination, heterogeneous catalysts offer a promising solution hindered by difficulties in atomic-scale structural characterization.
Through an innovative deposition-reduction approach, the team constructed precisely engineered 0.8–1.2 nm platinum bilayer clusters (Ptn/CeO2) on ceria nanorods. Advanced characterization combining aberration-corrected STEM imaging, quantitative electron microscopy simulations, and X-ray absorption spectroscopy unequivocally revealed the bilayer architecture: bottom-layer platinum atoms form strong interfacial bonds with the CeO2 support, while the top layer features coordinatively unsaturated metallic Pt⁰ active sites. This catalyst demonstrates exceptional performance in industrially vital anti-Markovnikov hydrosilylation, achieving 99.9% silane conversion with mass-specific activity far exceeding those of single-atom and nanoparticle catalysts, alongside 97.1% anti-Markovnikov selectivity. Remarkably, it retains 94% initial activity after 10 catalytic cycles—resolving the chronic deactivation problem in industrial systems.
Mechanistic studies via CO-DRIFTS, H2-TPR, and DFT calculations attribute this performance to strong silane adsorption at unsaturated Pt0 sites (-2.38 eV adsorption energy) and stable Pt-CeO2 interfacial bonding that prevents platinum leaching through enhanced metal-support interactions. This work establishes a new paradigm for atomically precise catalyst design with transformative potential for sustainable chemical manufacturing.