Thermal Transformations of Self-Assembled Gold Glyconanoparticles Probed by Combined Nanocalorimetry and X-ray Nanobeam Scattering

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• 作者：Christian Riekel ; Emanuela Di Cola ; Michael Reynolds ; Manfred Burghammer ; Martin Rosenthal ; David Doblas ; Dimitri A. Ivanov
• 刊名：Langmuir
• 出版年：2015
• 出版时间：January 13, 2015
• 年：2015
• 卷：31
• 期：1
• 页码：529-534
• 全文大小：425K
• ISSN：1520-5827

文摘

Noble metal nanoparticles with ligand shells are of interest for applications in catalysis, thermo-plasmonics, and others, involving heating processes. To gain insight into the structure-formation processes in such systems, self-assembly of carbohydrate-functionalized gold nanoparticles during precipitation from solution and during further heating to ca. 340 掳C was explored by in situ combination of nanobeam SAXS/WAXS and nanocalorimetry. Upon precipitation from solution, X-ray scattering reveals the appearance of small 2D domains of close-packed nanoparticles. During heating, increasing interpenetration of the nanoparticle soft shells in the domains is observed up to ca. 81 掳C, followed by cluster formation at ca. 125 掳C, which transform into crystalline gold nuclei at around 160 掳C. Above ca. 200 掳C, one observes the onset of coalescence and grain growth resulting in gold crystallites of average size of about 100 nm. The observed microstructural changes are in agreement with the in situ heat capacity measurements with nanocalorimetry.