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SSCI-VIDE+CDURABLE+SMR:BPU; International audience; A major challenge in the field of upconverting (UC)nanomaterials is to enhance upconversion luminescence. In comparison to conventional luminophores, quantum yields of lanthanide-doped UC nanoparticles are extremely low (typically less than 1%) and, in general, about an order of magnitude lower than those of corresponding UC bulk materials. It is well-known that –OH defects in the nanocrystals are the primary cause of upconversion quenching. We have employed designed anhydrous molecular precursors as a synthetic strategy to enhance upconversion efficiency in Yb and Tm co-doped MM'F nanocrystals (M = Li, Na; M' = Y, Gd). The bottom-up synthesis not only facilitates a better control over the composition, structure and morphology of the nanomaterials, but anhydrous conditions also minimize –OH functionality on the surface of the upconverting NPs. A detailed up-conversion studies reveal that the uniform nanoparticles obtained from these anhydrous single source precursors had i) superior up-conversion intensity than the UC materials produced from the hydrated inorganic salts, and ii) a comparable efficiency with bulk materials of the same composition. The applications of thesenanomaterials in the field of photocatalysis will be described.

SSCI-VIDE+CDURABLE+BPU:SMR; International audience; A major challenge in the field of up-conversion nanomaterials (UC) is the search for improved up-conversion luminescence. Compared to conventional luminophores, the quantum yields of lanthanide-doped nanoparticles are extremely low (typically

International audience; The paper presents the synthesis and characterization by electrical conductivity measurements, UV-Vis and FTIR spec-tra of two new chemical species obtained in MCl2⋅ xH2O (M = Cu, x=2; M= Mn, x=4)- N,N’-ethylenebisacetamide (EBA) – ethanol system. The X-ray structural analysis of two compounds – inorganic-organic cocrystals comprising of neutral 1D-inorganic polymeric chains {MCl2(H2O)2}n (M=Cu(II), Mn(II)), N,N’-ethylenebisacetamide (EBA) molecules and solvent ethanol molecules (1 and 2 respectively). Although the composition of cocrystals is very similar MCl2(H2O)2⋅EBA⋅0.5C2H5OH and differs only by metal (copper or manganese) they crystallize in different space groups. The copper(II) and manganese(II) ions have distorted octahedral surrounding completed by four chlorine atoms and two water molecules. The octahedrons form one-dimensional chains by Cl – Cl edge sharing. Organic molecules connect these chains in 3D- channel network via O–H···O and N–H···Cl hydrogen bonds.