Nd2O3/Au nanocomposites: upconversion broadband emission and enhancement under near-infrared light excitation

Abstract

In the present work, a novel strategy for the synthesis of Nd₂O₃/Au nanocomposites was successfully applied by a co-precipitation process, in which the upconversion luminescence (UCL) of Nd₂O₃ was a white broadband emission under 780–980 nm excitation. UCL enhancement in Nd₂O₃/Au nanocomposites with different doped concentrations of Au nanorods (NRs) under 980 nm and 808 nm excitation was systemically studied. It was observed that by the interaction of Nd₂O₃ with surface plasmon (SP) of Au NRs, the threshold power for generating broadbands was largely suppressed in contrast to the Nd₂O₃ nanoparticles (NPs). Further, it was interesting to observe that the enhancement was strongly dependent on the doped concentration of Au NRs and the excitation power of 980 nm and 808 nm laser diodes. The optimum UCL enhancement was 11-fold and 9-fold at 980 nm and 808 nm excitation, respectively. In addition, the upconversion (UC) broadband emission and UCL enhancement mechanism of Nd₂O₃/Au nanocomposites were proposed.