Nanoparticles of silver and gold decorated with platinum for applications in catalysis

• Grant number: 14/00427-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2014
• End date: March 31, 2015
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Pedro Henrique Cury Camargo
• Grantee: Mariana Cristina dos Santos Gonçalves
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

This project proposes to obtain a class of bimetallic nanostructures described by a core of silver ( Ag ) or gold ( Au ) decorated with platinum ( Pt ) with control over uniformity , morphology , size and composition . Specifically , we are interested in obtaining nanodendritas composed of silver -platinum ( Ag - Pt ) and gold -platinum ( Au - Pt ) for applications in heterogeneous catalysis . In the first stage of this study the focus will be the synthesis and characterization of Ag and Au nanospheres having diameters of 20-60 nm . Such nanospheres , in turn , be used as templates for the physical deposition of the second metal ( platinum ) ions by reducing their PtCl62 - producing nanostructures Ag- Au- Pt and Pt . In a later step , the catalytic activities of nanostructure Ag- Pt and Au - Pt opposite the reduction reaction of 4 - nitrophenol will be investigated as a model system , evaluating the influence of parameters such as the composition and structure of the nanoparticles in the catalytic activities of the same . By manipulating variables such as the molar ratio between the cores of Ag and Au precursor and the amount of platinum added to the reaction, among others , it is possible to control the composition and morphology of nanodendritas of interest, which by having branched structures and porous , large surface areas and small dimensions of each individual branch on the dendrites (<10 nm) show great promise for applications in catalysis.