Up-conversion study of CaF2 based oxy-fluoride core-shell particulate nano-glass ceramics via sol-gel method: Effect of Yb3+ concentration and cell viability study

Abstract

The current study delineates the synthesis and characterization of CaF2 based Oxy-fluoride glass-ceramics with Erbium (1 mol%) and with varying Ytterbium concentration (1 mol% and 5 mol%) doping of fluoride source. The influence of yb3+ concentration on thermal, structural, and luminescence properties were investigated and analyzed through a sol-gel process. The differential thermal analysis (DTA) specified that the glass transition (Tg) temperature decreases with the increase of Yb3+concentration in the prepared glass-ceramics. The microstructural study performed by transmission electron microscope (TEM), indicates the core-shell structure of glass-ceramics nanoparticles in between 10–50 nm range. The incorporation of Er3+ and Yb3+ into the crystalline matrix was confirmed and analyzed from X-ray diffraction (XRD) analysis. The increased crystal size according to increased temperatures shows the CaF2 crystal growth. The up-conversion luminescence properties of the prepared nano-glass ceramics were tested by using a 980 nm laser. The photoluminescence emission showed two peaks at green (548 nm and 528 nm) emission and one at red emission (626 nm). Additionally, the cell viability study of the Er3+-Yb3+ doped CaF2 nano glass-ceramics was performed using MG-63 osteoblast cells and it shows significant cell growth as compared to control over a period of 24 h. The result confirmed that the prepared nano-glass-ceramics can be a potential optical material for bio-imaging.