Premium
Shape Changes of Pt Nanoparticles Induced by Deposition on Mesoporous Silica
Author(s) -
Giovanetti Lisandro J.,
RamalloLópez José M.,
Foxe Michael,
Jones Louis C.,
Koebel Matthias M.,
Somorjai Gabor A.,
Craievich Aldo F.,
Salmeron Miquel B.,
Requejo Félix G.
Publication year - 2012
Publication title -
small
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.785
H-Index - 236
eISSN - 1613-6829
pISSN - 1613-6810
DOI - 10.1002/smll.201101293
Subject(s) - small angle x ray scattering , extended x ray absorption fine structure , xanes , radius of gyration , materials science , mesoporous silica , transmission electron microscopy , nanoparticle , mesoporous material , absorption (acoustics) , grazing incidence small angle scattering , chemical engineering , deposition (geology) , scattering , platinum , crystallography , analytical chemistry (journal) , nanotechnology , absorption spectroscopy , small angle neutron scattering , chemistry , polymer , composite material , neutron scattering , spectral line , optics , organic chemistry , engineering , biology , paleontology , catalysis , physics , astronomy , sediment
Abstract Polyvinylpyrollidone (PVP)‐capped platinum nanoparticles (NPs) are found to change shape from spherical to flat when deposited on mesoporous silica substrates (SBA‐15). Transmission electron microscopy (TEM), small‐angle X‐ray scattering (SAXS), and extended X‐ray absorption fine structure (EXAFS) analyses are used in these studies. The SAXS results indicate that, after deposition, the 2 nm NPs have an average gyration radius 22% larger than in solution, while the EXAFS measurements indicate a decrease in first neighbor co‐ordination number from 9.3 to 7.4. The deformation of these small capped NPs is attributed to interactions with the surface of the SBA‐15 support, as evidenced by X‐ray absorption near‐edge structure (XANES).