1 research outputs found

    High-performance Er3+TiO2 system: Dual up-conversion and electronic role of the lanthanide

    No full text
    Erbium-doped TiO2 materials are synthesized by means of a surfactant-free hydrothermal method having good photoactivities for the liquid-phase degradation of phenol and MB and the gas phase of toluene. From the structural and morphological characterization, it has been stated that the presence of Er3+ induces a progressive anatase cell expansion due to its incorporation in the TiO2 lattice. The best photocatalytic performance was attained for the samples with 2 at% of Er3+ irrespective of the chemical degradation reaction essayed. From activity and optical studies under different irradiation excitation conditions, a dual-type mechanism is proposed to be at the origin of the photocatalytic activity enhancement. On one hand, the improvement observed under UV irradiation occurs by the effective charge separation promoted by Er3+ species which would act as electron scavenger. Besides, the up-conversion luminescence process of Er3+ allows profiting the NIR range of the lamp and transferring energy in the UV range to the TiO2. The dual action of Er ions located at anatase networks will open up a wide roadway for the developing of an integral solar active photocatalyst. 2012 Elsevier Inc. All rights reserved.The financial support by projects P09-FQM-4570, CTQ2010-14872/BQU and ENE2011-24412 is fully acknowledged. S. Obreg贸n Alfaro thanks CSIC for the concession of a JAE-Pre grant. A. Kubacka thanks Spanish MINECO for a Post-doctoral Raman y Cajal fellowship. We also thanks to M. Calvo and H. M铆guez for PL measurements.Peer Reviewe
    corecore