Insight into growth of Au – Pt bimetallic nanoparticles: an in   situ XAS study

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 L3-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.
Source: Journal of Synchrotron Radiation - Category: Physics Authors: Tags: XAS in   situ EXAFS XANES core – shell research papers Source Type: research

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Source: Current Nutrition and Food Science - Category: Nutrition Source Type: research
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Source: Dental Press Journal of Orthodontics - Category: Dentistry Source Type: research
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Source: Materials Research Bulletin - Category: Materials Science Source Type: research
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Source: Journal of Materials Research and Technology - Category: Materials Science Source Type: research
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Source: The American Journal of Geriatric Psychiatry - Category: Psychiatry Tags: Am J Geriatr Psychiatry Source Type: research
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Source: Journal of Synchrotron Radiation - Category: Physics Authors: Tags: coherence imaging microscopy research papers Source Type: research
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Source: Food Microbiology - Category: Food Science Authors: Tags: Food Microbiol Source Type: research
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Source: Food Microbiology - Category: Food Science Authors: Tags: Food Microbiol Source Type: research
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