Abstract
Nanospherical upconversion luminescence particles (UCLPs) Gd2O3:Er3+ and Gd2O3:Er3+@ chitosan (CS) were prepared by step-by-step precipitation and calcination of the available nitrate rare Earth sales and chitosan. The morphology and composition of as-prepared samples were characterized by field emission electron spectroscopy (FESEM) and Fourier transform infrared (FT-IR) spectroscopy. The synthesized UCLPs were non-agglomerate spheres in uniform nanoscale. The quantitative amount of chitosan was well coated with the gain surface of the UCLPs Gd2O3:Er3+ to obtain Gd2O3:Er3+@CS nanocomposite. The down-conversion luminescent intensity of Gd2O3:Er3+ NSP is lower than Gd2O3:Er3+@CS NSP samples, but luminescent characterizations were non-change. The photoluminescence (PL) of the green emission range of all UCLPs samples with chitosan-coated and -uncoated took the leading position. By using a diode laser excitation with 975 nm of wavelength, the detected intensity of red emission is more remarkably detected than green emissions. The two-photon mechanism for both green and red emissions of nanophosphor was observed. As a result, these might be promising opportunities to conjugate with various bio subjects that could be used in medical applications.
Funder
Vietnam National Foundation for Science and Technology Development
Publisher
The Electrochemical Society
Subject
Electronic, Optical and Magnetic Materials