Up-conversion luminescence properties of Yb 3+ –Ho3+ co-doped CaLa2ZnO5.

Abstract: A class of Yb3+/Ho3+ ions co-doped CaLa2ZnO5 (CLZ) up-conversion (UC) phosphors were synthesized by sol–gel method. Under 980nm excitation, UC spectra consist of two prominent emission bands centered at 545 and 662nm originating from 5F4, 5S2→5I8 and 5F5→5I8 transitions of Ho3+ ion, respectively. The UC spectra as a function of the concentration of the dopants were also investigated to determine the optimal composition. The possible UC mechanism was proposed, and lifetime measurements were also carried out to support our proposal. [Copyright &y& Elsevier]