Optical properties of Ni2+ in ZrO2 nanocrystals

Ni2+ doped ZrO2 nanocrystals have been prepared by a urea-containing coprecipitation method. The photoluminescence of the doped samples was investigated in detail. Upon excitation at 483 nm, a red emission band at 612 nm was observed originating from the T-1(2) (D-1)-T-3(2) (F-3) transition of Ni2+. Effects of both heat-treated temperature and doping concentration on the luminescent properties were also studied. The results reveal that a concentration quenching of the luminescence occurs as the molar ratio of Ni2+ exceeds the optimum value (1%). However, no thermal quenching was observed probably due to the improved crystallinity of the host lattice resulting from the increase of the calcining temperature. (C) 2004 Elsevier B.V. All rights reserved.