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Photoluminescence (PL), PL lifetime, and radioluminescence (RL) measurements were made on LaF3 nanoparticles doped with Eu3+ or Sm3+. The radiative lifetimes decreased with increasing rare earth concentrations, which can be attributed to energy transfer to the surface of the nanoparticles followed by non-radiative recombination. The RL signal increases with increasing concentration for Eu3+ concentrations up to 20% Eu3+ but it saturates and disappears for >10% Sm3+. A dose-independent RL was observed up to 10 kGy during continual X-ray irradiation for Eu3+ and Sm3+ doped nanoparticles, which is advantageous for real time dosimetry applications (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

We report the dramatic effect of rationally-designed phosphopeptides on the size and shape of iron-iron oxide core-shell nanoparticles prepared in a one-pot synthesis by sodium borohydride reduction of an iron salt. These phosphopeptides are effective at small ratios of peptide to metal, in contrast to the behaviour of conventional capping agents, which must be added at high concentration to control the particle growth. Wet chemical techniques are attractive methods for the preparation of metal nanoparticles. Here, we report the dramatic effect of rationally-designed phosphopeptides on the size, shape and magnetic properties of iron-iron oxide core-shell nanoparticles prepared in a one-pot synthesis by sodium borohydride reduction of an iron salt. These phosphopeptides are effective at small ratios of peptide to metal, in contrast to the behaviour of conventional surfactants, which must be added at high concentration to control the particle growth. [ABSTRACT FROM AUTHOR]

This Communication describes the synthesis of highly monodispersed 12 nm nickel nanocubes. The cubic shape was achieved by using trioctylphosphine and hexadecylamine surfactants under a reducing hydrogen atmosphere to favor thermodynamic growth and the stabilization of {100} facets. Varying the metal precursor to trioctylphosphine ratio was found to alter the nanoparticle size and shape from 5 nm spherical nanoparticles to 12 nm nanocubes. High-resolution transmission electron microscopy showed that the nanocubes are protected from further oxidation by a 1 nm NiO shell. Synchrotron-based X-ray diffraction techniques showed the nickel nanocubes order into [100] aligned arrays. Magnetic studies showed the nickel nanocubes have over 4 times enhancement in magnetic saturation compared to spherical superparamagnetic nickel nanoparticles. [ABSTRACT FROM AUTHOR]