Damien Chaudanson | Searcharxiv

arXiv2013

Silicon Sheets By Redox Assisted Chemical Exfoliation

In this paper, we report the direct chemical synthesis of silicon sheets in gram-scale quantities by chemical exfoliation of pre-processed calcium di-silicide (CaSi2). We have used a combination of X-ray photoelectron spectroscopy, transmission electron microscopy and Energy-dispersive X-ray spectroscopy to characterize the obtained silicon sheets. We found that the clean and crystalline silicon sheets show a 2-dimensional hexagonal graphitic structure.

physics.chem-ph↗

arXiv2013

Copper red glazes: a coating with two families of particles

In order to explain the origin of the deep red color of copper glazes on ceramics, a ceramist has elaborated, by firing under reducing atmosphere, a significant number of tiles. The analysis of the structure and composition of a representative sample by TEM and EELS, followed by an optical characterization and an optical modeling using the radiative transfer approach (four-flux model) have enabled a comprehensive explanation of the origin of the color in these glazes. The presence of two families of copper nanoparticles in the vitreous matrix. The first, purely absorbing, of diameter 10-50 nm, essentially creates color by a substractive process. The second, due to its larger diameter, 100 nm or more, mainly acts on color by scattering of the visible light. Both act competitively in the layer. A color chart of all the hues which can be reached by this technique has eventually been theoretically calculated.

physics.optics↗