Augmented photocatalytic activity and luminescence response of Tb3+ doped nanoscale titania systems

作者：Paul Nibedita; Deka Amrita; Mohanta Dambarudhar^*

来源：Journal of Applied Physics, 2014, 116(14): 144902.

DOI：10.1063/1.4897369

The present work reports on the effect of Tb3+ doping on the luminescence and photocatalytic performance of nano-structured titania derived through a sol-gel route. X-ray diffraction patterns have revealed the existence of anatase phase with and without Tb3+ doping and with an improved orientation factor along (004) and (200) planes. Transmission electron microscopy and selective area electron diffraction studies, while exhibiting ample poly-crystallinity feature, have predicted an average particle size of similar to 9 nm and similar to 6 nm for the un-doped and 5% Tb3+ doped nano-titania samples; respectively. Apart from emissions accompanied by different types of defects, Tb3+ related transitions, such as, D-5(3) > F-7(5), D-5(3) > F-7(4), and D-5(4) > F-7(6) were identified in the photoluminescence spectra. Brunauer-Emmett-Teller surface area analysis, as carried out on a Tb3+ doped nano-titania system, has demonstrated a more-open hysteretic loop owing to significant difference of N-2 adsorption/desorption rates. The photocatalytic activity of nano-titania, as evaluated from the nature of degradation of methyl orange under UV illumination, exhibited the highest efficiency for a Tb3+ doping level of 2.5%. The augmented photocatalytic degradation has also been discussed in the light of a model based on pseudo first-order kinetics.

• 出版日期2014-10-14