Stéphane Jobic (DR), Martine Bujoli-Doeuff (MC), Mayte Caldes (CR), Philippe Deniard (DR), Camille Latouche (MCF).
A pigment absorbs light in the visible range (400 nm <λ <800 nm), a UV absorber beyond (λ <400 nm). Both are the seat of electronic transitions which, depending on their positioning in energy and their intensity, will give rise to colored materials with varying degrees of coloring power, their colorimetric characteristics being obviously strongly affected by their granulometry, morphology and Surrounding environment.
In addition to the synthesis of new materials, which is the first priority of our research activity, determining the nature of these transitions is essential in order to be able to model them and thus to reasonably synthesize the material with the desired properties. To date, we are always looking for new pigments for the replacement of materials based on heavy elements (e.g. lead, mercury) or proven toxicity (e.g., antimony, arsenic). In this context, the synthesis of inorganic materials having a red coloring similar to Ferrari red is a Grail.
The search for new pigments yellow is also still relevant to replace BiVO4, which itself to supplant CdS. At the same time, the discovery of compounds green, blue, etc. distinguishing themselves from their mates can always give rise to a potential industrialization. Concerning UV absorbers, the main objective is to protect human tissue, wooden or plastic object from the solar radiation without inducing parasitic coloring. This is antinomic constraints that often require very specific shaping of the particles to minimize diffusion phenomena or the use of materials with low refractive index (e.g. organic-inorganic hybrid materials).
|Red and yellow pigments based on Ce3 +|
|Correlation between absorption and diffusion|
|Evolution of the refractive index as a function of the capacity of the material under consideration to absorb light|
Current: Stéphane Jobic (DR), Martine Bujoli-Doeuff (MC), Mayte Caldes (CR) , Philippe Deniard (DR), Camille Latouche (MCF)
Past: Rémi Dessapt (MC), Xavier Rocquefelte (Pr. à l’Univ. de Rennes 1 depuis Sept. 2014), Gilles Gauthier, Fabrice Goubin, Daniel Kervern
CePS4 Electronic Structure and Optical Properties
G. Gauthier, S. Jobic, F. Boucher, P. Macaudière, D. Huguenin, J. Rouxel, R. Brec
Chem. Mater., 10, 2341-2347, 1998
Syntheses, Structures and Optical Properties of Yellow Ce2SiS5, Ce6Si4S17 and Ce4Si3S12 Materials
G. Gauthier, M. Evain, S. Jobic, R. Brec, M.-H. Whangbo, C. Fouassier
Chem. Mater., 15, 828-837, 2003
Experimental and Theoretical Characterization of the Optical Properties of CeO2, SrCeO3 and Sr2CeO4 containing Ce4+ (f0) ions
F. Goubin, X. Rocquefelte, M.-H. Whangbo, Y. Montardi, R. Brec, S. Jobic
Chem. Mater., 16, 662-669, 2004
Investigation of the Origin of the Empirical Relationship between Refractive Index and Density on the basis of First Principles Calculations for the Refractive Indices of various TiO2 Phases
X. Rocquefelte, G. Goubin, S. Jobic, H.-J. Koo and M.-H. Whangbo
Inorg. Chem., 43, 2246-2251, 2004
Analysis of the refractive indices of TiO2, TiOF2, and TiF4: Concept of optical channel as a guide to understand and design optical materials
X. Rocquefelte, F. Goubin, Y. Montardi, N. Viadere, A. Demourgues, A. Tressaud, M-H. Whangbo, S. Jobic
Inorg. Chem., 44, 3589-3593, 2005
On the volume-dependence of the index of refraction from the viewpoint of the complex dielectric function and the Kramers-Kronig relation
X. Rocquefelte, S. Jobic, M. Whangbo
J. Phys. Chem. B, 110, 2511-2514, 2006
Concept of optical channel as a guide for tuning the optical properties of insulating materials
X. Rocquefelte, S. Jobic, M-H. Whangbo
Solid State Sci., 9, 600-603, 2007
How does synthesis temperature impact hybrid organic-inorganic molybdate materials design?
R. Dessapt, D. Kervern, M. Bujoli-Doeuff, P. Deniard, S. Jobic
Inorg. Chem., 49, 11309-11316, 2010
- Pr. M. Whangbo, Department of Chemistry, North Carolina State University, Raleigh (USA)
- Pr. C. Andraud, Centre de recherche sur la conservation des collections, USR3224 CRC, Muséum national d’histoire naturelle, Paris
ANR and contracts
- Industrial contracts with Rhodia Electronics & Catalysis and Lapeyre
- Academic contract "Technological Innovation Research Network Materials and Processes"
- "Application du concept d'effet inductif à la recherche de nouveaux pigments chalcogénés à base de cérium", Gilles Gauthier, 1999
- "Relation entre fonction diélectrique et propriétés optiques: application à la recherche d’absorbeurs UV inorganiques de deuxième génération", Fabrice Goubin, 2003
- "Synthèse et caractérisation d'absorbeurs UV de seconde génération pour la protection des bois ", Daniel Kervern, 2011