**3. Result and discussion**

### **3.1 XRD result**

The XRD pattern of the Gd2O3 sample is shown in **Figure 3**. The diffraction patterns are well matched with standard JCPDS card no. 43-1015, indicating that the sample of Gd2O3 phosphor is in the pure monoclinic phase. The particle size was calculated by the Scherer formula [7] *<sup>D</sup>* = \_*<sup>k</sup>*

$$D = \frac{k\lambda}{\beta C \alpha \theta} \tag{1}$$

**81**

**Figure 4.**

*Gd2O3: A Luminescent Material*

of nano range.

**3.3 TEM result**

particle for both fuels [1, 2, 7].

**3.4 Energy dispersive X-ray analysis (EDX)**

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

The signs that get from electron and sample interaction uncover data about the example including outer morphology, elemental composition, and crystalline structure and introduction of materials making up the example. The SEM is likewise fit for performing examinations of chose point areas on the example; this methodology is particularly valuable in subjectively or semi-quantitatively deciding synthetic structures. **Figure 4** demonstrates the SEM micrographs of the Gd2O3 arranged by combustion synthesis method utilizing urea and glycine as a fuel. The black and white SEM micrograph of the prepared powder indicates that all the particles are looking like agglomerated in homogeneously in different shapes/sizes of the order

Transmission electron microscopy (TEM) is an imaging system whereby a light emission is engaged onto an example making a broadened form show up on a fluorescent screen or layer of photographic film or to be distinguished by a CCD camera. The main commonsense transmission electron magnifying instrument was built by Albert Prebus and Lames Hillier at the college of Toronto in 1938 utilizing ideas grew before by Max Knoll and Ernst Ruska. The particle size of the system was determined by high resolution transmission electron microscopy (HRTEM). It is a phase differentiated imaging process because the image formed is due to the scattering of electron waves through a thin surface. In **Figure 5**, HRTEM micrograph demonstrates a Gd2O3 nanocrystal with a width of 8–10 nm seen all through the

Elemental investigation of the prepared samples is generally determined by EDX analysis. The spectrum shows the relation between the X-ray energy, which lies in between 10 and 20 eV, and the number of counts per channel by a plot between them in X and Y axes, respectively. An X-ray line is expanded by the reaction of the framework, delivering a Gaussian profile. Energy resolution is characterized as the full width of the crest at half maximum height (FWHM). In the spectrum of both the Gd2O3 samples, intense peak of Gd and O is present, which confirms the formation of Gd2O3 phosphor (**Figure 6**). For EDX analysis, the entire area of the black and white SEM micrographs was analyzed with EDX mapping and spectrum. The

*Scanning electron microscope image of Gd2O3 phosphor: (A) glycerin fuel and (B) urea fuel.*

where *D* is the volume weighted crystallite size, *k* is the shape factor (0.9), *λ* is the wavelength of Cu Kα1 radiation, *β*hkl is the instrumental corrected integral breadth of the reflection (in radians) located at 2*θ*, and *θ* is the angle of reflection (in degrees) utilized to relate the crystallite size to the line broadening. The average crystallite size of Gd2O3 nanoparticles was found to be in the range of 8–10 nm for both the fuels. No impurity peaks or other possible phases of Gd2O3 were observed. Further, the strong and sharp diffraction peaks confirm the high crystallinity of the products.

### **3.2 Surface morphology**

The scanning electron microscopy (SEM) was utilized as a focused ray of high energy electrons to produce an assortment of signs at the crystalline surface.

**Figure 3.** *XRD patterns of Gd2O3: (A) glycerin fuel and (B) urea fuel.*
