Relaxation dynamics of processes in colloidal zirconia nanosols. Dependence on excitation energy and temperature

This Letter addresses process relaxation dynamics occurring in colloidal zirconia (ZrO2) nanosols under steady-state and pulsed laser excitation; the temperature dependence of the photoluminescence is also reported. The laser-induced emission emanating from these nanosols is thermally quenched with activation energy E-tq = 0.048 +/- 0.008 eV, identical to the activation energy (E-tq = 0.050 +/- 0.005 eV) of thermal quenching of the photoluminescence under steady-state excitation. It is also identical to the energy (E-ads = 0.046 +/- 0.005 eV) of thermal quenching of the photostimulated adsorption of oxygen on ZrO2 micron-size particles. A pathway to summarize the events is proposed. (C) 2001 Published by Elsevier Science B.V.