Synthesis and Characterization of Dendrimer-Encapsulated Bimetallic Core-Shell PdPt Nanoparticles

Using a successive method, PAMAM dendrimer-encapsulated bimetallic PdPt nanoparticles have been successfully prepared with core-shell structures （Pd@Pt DENs）. Evidenced by UV-vis spectra, high resolution trans- mission electron microscopy, and X-ray energy dispersive spectroscopy （EDS）, the obtained Pd@Pt DENs are monodispersed and located inside the cavity of dendrimers, and they show a different structure from monometallic Pt or Pd and alloy PdPt DENs. The core-shell structure of Pd@Pt DENs is further confirmed by infrared measure- ments with carbon monoxide （IR-CO） probe. In order to prepare Pd@Pt DENs, a required Pd/Pt ratio of 1 ： 2 is de- termined for the Pt shell to cover the Pd core completely. Finally, a mechanism for the formation of Pd@Pt DENs is proposed.

树状大分子金属催化剂的研究进展

树状大分子模板金属催化剂是一种新型的均相、择型催化剂,综述了数年来以树枝状大分子为模板的各种金属催化剂的合成、表征及应用等方面的研究进展,介绍了催化剂的回收再利用方法,并对未来发展方向进行了展望。