SYNTHESIS AND OPTICAL PROPERTIES OF HYDROXYAPATITE MATERIAL (HA):Er, Yb ORIENTED TOWARDS APPLICATIONS IN OPTOELECTRONICS AND BIOMEDICINE

Abstract

In this work, we report the intense green upconversion (UC) emission in hydroxyapatite (HA):Er, Yb phosphor synthesized using the combustion method following heat treatment at 900 ℃ for 3 h in air. The material was characterized for its structure, morphology, elemental composition, and luminescent properties using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), and photoluminescence spectroscopy (PL). XRD results confirm the main phase hydroxyapatite (HA) and a tract amount of the tricalcium phosphate (β-TCP) phase with high crystallinity of the obtained material. EDS analysis shows that the presence of elements of the host lattice (Ca, P, O) and dopant ions (Er, Yb) and other impurities elements did not appear. Under 975 nm excitation, the obtained phosphor behave intense green emission at 530/554 nm and weak green emission at 660 nm of the Er³⁺ ion. The selective enhancement of red UC emission corresponds to an energy transfer from Yb³⁺ to Er³⁺ ions. The results indicate that HA:Er, Yb phosphor promising material for optoelectronics and biomedical applications.