**2. Materials and methods**

### **2.1 Synthesis**

Phosphor was synthesized by combustion synthesis method. Gadolinium nitrate was used as precursor solution and urea or glycine as fuel. Aqueous solution of gadolinium nitrate was prepared by dissolving suitable amount of precursor into

**79**

**Figure 2.**

*Gd2O3: A Luminescent Material*

**2.2 Material characterization**

over 5000 cm<sup>−</sup><sup>1</sup>

1 cm<sup>−</sup><sup>1</sup>

**Figure 1.**

steady at 300 W.

*DOI: http://dx.doi.org/10.5772/intechopen.92310*

double distilled water followed by the addition of fuel. The mixture was kept in a magnetic stirrer at 60°C and stirred for 4 h, and a transparent gel was obtained. Gel was transferred into alumina crucible and kept in a preheated furnace at 600°C. The gel mixture undergoes dehydration followed by spontaneous combustion to form Gd2O3 powder [1, 2]. The resulting brownish powder was heated until a controlled explosion took place yielding a very fine, white powder. Since the reaction is so

The crystallinity of the phosphor was checked by X-ray diffraction estimation. The X-ray powder diffraction information was gathered by utilizing Bruker D8 Advanced X-ray diffractometer using Cu Kα radiation. The X-beams were created utilizing a fixed cylinder, and the wave length of X-beam was 0.154 nm. The X-rays were identified utilizing a quick checking indicator dependent on silicon strip technology (Bruker Lynx Eye finder). The surface morphology of the phosphors was detected by field emission electron microscopy (FESEM) JSM-7600F. Energy dispersive X-ray examination (EDX) was utilized for compositional investigation of the phosphor. Crystal size of arranged phosphor was determined by Transmission Electron Microscopy (TEM) utilizing Philips CM-200. Raman spectra were recorded by Jobin-Yvon, France, Ramnor HG-2S Spectrometer with

CLAM2 analyzer and a twin Mg/Al anode. The weight pressure in the investigation chamber was roughly 9 × 10<sup>−</sup>10 mbar. The estimations were done with unmonochromated Al Kα photons (1486.6 eV). The intensity of the X-ray source was kept

and wave number exactness of

. XPS investigation was performed in a VG instrument with a

rapid, the crystal growth will be highly restrained (**Figures 1** and **2**).

Ar-Laser with 4 W control having goals of 0.5 cm<sup>−</sup><sup>1</sup>

*Flow chart of synthesis of Gd2O3 with urea (reproduced from [1]).*

*Flow chart of synthesis of Gd2O3 with glycerin (reproduced from [2]).*
