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RESEARCH PRODUCT
Sintering of copper nanopowders under hydrogen: an in situ X-ray diffraction analysis.
Frédéric BernardPascal PerriatN. Guigue-millotYannick Championsubject
Copper oxideCupriteMaterials scienceHydrogenAnalytical chemistrySinteringMineralogyNanoparticlechemistry.chemical_element02 engineering and technology[SPI.MAT] Engineering Sciences [physics]/Materials01 natural sciences[SPI.MAT]Engineering Sciences [physics]/Materialschemistry.chemical_compound0103 physical sciencesGeneral Materials ScienceComputingMilieux_MISCELLANEOUS010302 applied physicsMechanical Engineering021001 nanoscience & nanotechnologyCondensed Matter PhysicsEvaporation (deposition)CopperchemistryMechanics of Materialsvisual_artX-ray crystallographyvisual_art.visual_art_medium0210 nano-technologydescription
Abstract The reduction by hydrogen gas of the cuprite layer on copper nanocrystals and the subsequent sintering of the nano-particles were studied using in-situ X-ray diffraction and dilatometry. Spherical nanocrystals produced by evaporation and condensation have an average size of 35 nm, exhibiting a large surface curvature. Each nanoparticle is coated with a 3.5 nm layer of Cu 2 O, which is rough and disordered, as revealed by high-resolution electron microscopy. Reduction by hydrogen of this curved cuprite layer occurs at 363 K, which is ≈65 K lower than is observed on a layer supported by micrometer-sized or bulk copper with a flat surface. The reduction process and its effect on the sintering of nanopowders are analysed and discussed.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2003-11-01 |