Open AccessInsight into growth of Au–Pt bimetallic nanoparticles: an in situ XAS study
Author(s) -
Nayak Chandrani,
Bhattacharyya D.,
Bhattacharyya K.,
Tripathi A. K.,
Bapat R. D.,
Jha S. N.,
Sahoo N. K.
Publication year - 2017
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577517006257
Subject(s) - x ray absorption spectroscopy , extended x ray absorption fine structure , xanes , bimetallic strip , absorption spectroscopy , nanoparticle , x ray photoelectron spectroscopy , materials science , spectroscopy , absorption (acoustics) , analytical chemistry (journal) , chemistry , chemical engineering , nanotechnology , metal , organic chemistry , optics , physics , engineering , quantum mechanics , metallurgy , composite material
Au–Pt bimetallic nanoparticles have been synthesized through a one‐pot synthesis route from their respective chloride precursors using block copolymer as a stabilizer. Growth of the nanoparticles has been studied by simultaneous in situ measurement of X‐ray absorption spectroscopy (XAS) and UV–Vis spectroscopy at the energy‐dispersive EXAFS beamline (BL‐08) at Indus‐2 SRS at RRCAT, Indore, India. In situ XAS spectra, comprising both X‐ray near‐edge structure (XANES) and extended X‐ray absorption fine‐structure (EXAFS) parts, have been measured simultaneously at the Au and Pt L 3 ‐edges. While the XANES spectra of the precursors provide real‐time information on the reduction process, the EXAFS spectra reveal the structure of the clusters formed in the intermediate stages of growth. This insight into the formation process throws light on how the difference in the reduction potential of the two precursors could be used to obtain the core–shell‐type configuration of a bimetallic alloy in a one‐pot synthesis method. The core–shell‐type structure of the nanoparticles has also been confirmed by ex situ energy‐dispersive spectroscopy line‐scan and X‐ray photoelectron spectroscopy measurements with in situ ion etching on fully formed nanoparticles.