8 research outputs found
Room-Temperature Synthesis of Iron-Doped Anatase TiO2 for Lithium-Ion Batteries and Photocatalysis
International audienceIron-doped nanocrystalline particles of anatase TiO2 have been successfully synthesized using a complete room-temperature synthetic approach, leading to particles of high surface area (280 m2/g) and a narrowed band gap of 2.3 eV. These particles were introduced for photocatalysis under white light in standard conditions (AM1. 5G) and in lithium-ion batteries to reveal in these two aspects the pros and cons of the doping effect
Effect Of Nanoparticle Size on The Photoelectrochemical Property of Anatase Nanocrystals in Photocatalysis
Using light energy to make electrochemical reaction, photocatalysis is among the most promising technology for water treatment. In heterogeneous catalysis, electrochemical reactions occur at the liquid/solid of gas/solid interface. The development of materials with a high surface area (nanomaterials) has then been considered as the best route achieving an efficient system. In this paper, we studied the effect of the crystal size on the photoelectrochemical properties of anatase. Two synthesis routes were used to get nanoparticles with different size and the comparison of their efficiency for the degradation of rhodamine B under ultraviolet (UV) light excitation showed that crystallite size is most important than surface area consideration. Comparing results obtained under UV lamp and under sunlight excitation, we also demonstrated that photocatalysis is more efficient under sunlight radiation
Nanoparticulate Coatings with Efficient Up-Conversion Properties
International audienceNanoparticulate films with high up-conversion emission (UC) properties were prepared by spray-deposition of nanometer-sized YVO 4 :Yb,Er particles. The optical properties of YVO 4 :Yb,Er were optimized upon annealing before the film deposition in order to get the highest possible UC signal in the considered type of system. Thanks to a simple model and some time-resolved spectroscopic investigations, the contribution of the scattering to the UC signal could be separated from the intrinsic properties (crystallinity, surface defects) of the material. The films obtained by this technique present the advantages of having both high UC and good transparency