Here we describe the first seedless synthesis of vinyl-terminated Au nanotriangular prisms (AuNTPs) and nanooctahedra (AuNOC) in aqueous media. This synthesis is performed by chemical reduction of chloroauric acid (HAuCl4) with 3-butenoic acid (3BA) in the presence of benzyldimethylammonium chloride (BDAC). The principal novelties of the presented method are the use of a mixture of 3BA and BDAC, the synthesis of gold prisms and octahedra with controllable size, and the presence of terminal double bonds on the metal surface. Initially this method produces a mixture of triangular gold nanoprisms and octahedra; however, both morphologies are successfully separated by surfactant micelle induced depletion interaction, reaching percentages up to ∼90%. Moreover, the alkene moieties present on the gold surface are exploited for the fabrication of hybrid core@shell particles. Gold octahedra and triangular prisms are easily encapsulated by free radical polymerization of N-isopropylacrylamide (NIPAM). Finally, in order to obtain a gold core with the most number of tips, AuNTP@pNIPAM microgels were subjected to gold core overgrowth, thus resulting in star-shaped nanoparticles (AuSTs@pNIPAM). We use 4-amino-benzenethiol as the model analyte for SERS investigations. As expected, gold cores with tips and high curvature sites produced the highest plasmonic responses.

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Here we report the synthesis and characterization of several tripod-shaped oligo(p-phenylene)s molecules with legs composed of five and three phenylene units, compounds 1 and 2,r espectively.I nt heses tructures, each leg is end-capped with an azide group andt he terminal functional arm contains an acetylene or bromine group. The presented synthesis has as the key step aP d-catalyzedS uzukic rosscoupling reaction. In particular,t he iodine derivative from the silicon core molecule reacts with the appropriate oligo(p-phenylene) boron derivative, thus generating the final tripod-shaped structure. The azide end-capped leg is specifically designed for its covalentincorporation on alkynyl terminated silicon surfaces in an easy and reproducible way. As ap reliminarys tudy,w ep resent the nanostructuration of tripod 2a on alkynyl-functionalized silicon waferst hrough copper-catalyzed alkyne-azide cycloaddition (CuAAC) click reaction.