title: Au nanoparticles encapsulated in Ru carbonyl carboxylate shells.
abstract: A two-step surface functionalization approach has been used to encase Au nanoparticles in monolayer organometallic Ru-complex shells by the reaction of an intermediate surface-bound mercaptopropanoic acid capping species with Ru dodecacarbonyl (Ru3(CO)12) clusters. Vibrational (infrared and Raman) spectroscopy shows that insertion of carboxylate groups into the Ru clusters results in their fragmentation and the formation of a shell of Ru dicarbonyl carboxylate oligomers that remain attached to the Au nanoparticles through the original Au-alkanethiolate bonds. The structural integrity of the metallic nanoparticulate Au cores has been verified by X-ray photoelectron spectroscopy, X-ray diffraction, and transmission electron microscopy. The organometallic Ru-complex shell may be decomposed thermally to eliminate the mercaptopropanoate and carbonyl groups and leave a mixed phase of Au and RuO2.
authors.affiliation: Department of Chemistry, National University of Singapore, Kent Ridge, Singapore 119260, Singapore.
authors.forename: Suhua
authors.initials: S
authors.lastname: Wang
authors.forename: Wee-Sun
authors.initials: WS
authors.lastname: Sim
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D003460:Crystallization; D004583:Electrons; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D046529:Microscopy, Electron, Transmission; D015394:Molecular Structure; D010316:Particle Size; D012428:Ruthenium / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D014732:Vibration; D014961:X-Ray Diffraction
chemical_list: D002264:Carboxylic Acids; D013438:Sulfhydryl Compounds; D006046:Gold; D012428:Ruthenium