Effect of Cobalt doping on luminescence properties of gadolinium aluminum garnet

The luminescent properties of GAG: Co (Gd3Al5O12:Co) arises from the absorption of light in the visible and near-infrared regions by the Co ions. When excited by light, the Co ions can transfer their energy to other ions in the material, which can emit light of a different color. The color of the emitted light depends on the specific energy levels of the ions involved in the luminescent process. In GAG: Co, the emitted light is typically in the blue-green region of the spectrum. A series of singly doped gadolinium aluminum garnet with cobalt (GAG: Co) of different concentrations were synthesized by the sol–gel method after sintering at a temperature 1100 ℃. The X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) show the precipitation of GAG: Co with a size around 25–40 nm and phase formation was acknowledged by X-ray Diffraction. Fourier infrared transformation spectroscopy (FTIR) analysis gives the system evaluation and composition of a material. Energy Dispersive X-ray (EDX) analysis confirms the incorporation of Cobalt ions in GAG. The luminescence properties of the material were investigated by FTIR, UV–Vis spectroscopy, and Fluorescence spectroscopy. Analyses of FTIR were also supportive of XRD results. Emission spectra were determined for excitations 270 nm and 282 nm and lifetime was found to decrease with an increase in doping concentration. The material shows mixed color components on the chromaticity diagram which makes it a supportive material for application in white light sources.