Up-conversion nanoparticles

Macroemulsion-derived nanoparticles without compaction can also find use as shown in specific cases. Erbium-doped zirconia particles in the size range of 25-50 nm were synthesized by Patra et al, [184], who showed improved optical up-conversion in these powders. 

Sivakumar S, Boyer J-C, Bovero E, van Veggel FCJM (2009) Up-conversion of 980 nm light into white light from sol-gel derived thin film made with new combinations of LaF3 Ln nanoparticles. J Mater Chem 19 2392-2399... 

Lu, H., Yi, G., Zhao, C., Chen, D., Liang-Hong, G., and Cheng, J. 2004. Synthesis and characterization of multi-functional nanoparticles possessing magnetic, up-conversion fluorescence and bio-affinity properties. J. Mater. Chem. 14 1336-1341. 

Changes in thermal stability and mass due to the formation of CdS nanoparticles in LB films were examined [180]. The LB films were formed onto gold-coated quartz oscillators from monolayers of arachidic acid or nonacosa-10,12-diynoic acid on CdCH containing subphases. The films were exposed to H2S gas until the mass change indicated complete conversion of Cd to CdS. The thermal stability of the H2S-treated films was reduced, with significant mass loss initiating at 55°C, compared to minimal mass loss in the untreated films up to at least 80°C under mild vacuum. The average CdS-particle size... 

Recently, platinum nanoparticles protected by N,N-dimethyl-N-cetyl-N-(2-hydro-xyethyl)ammonium chloride salt and modified with cinchonidine were investigated in the enantiomeric hydrogenation of ethyl pyruvate in pure biphasic liquid-liquid (water/substrate) media at room temperature [139]. For the first time, the aqueous phase containing Pt(0) nanocatalysts with an average size of 2.5 nm could be reused for successive hydrogenations, and with a total conversion of activity and enantioselectivity in (R)-(+)-ethyl lactate up to 55% (Scheme 9.12). 

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