Synthesis of Zinc Oxide Nanoparticles through the Chemical, Green methods and their environmental pollutants remediation

Abstract

The present research work Zinc Oxide nanoparticles (ZnO NPs) synthesized by green method and chemical methods. Zinc Oxide nanoparticles is to prepare eco-friendly nature and without using any toxic chemicals, hazardous solvents. The ZnO nanoparticles were characterized using different host of analytical technique, form the UV-Vis spectroscopy to conform the formation of the nanoparticles, the characteristic absorption band around 340-360 nm.  Size and morphology identify by the transmission electron microscopy (TEM), in the case of green method particles are spherical nature and in the case of chemical method particles are square shape nature was obtained. Crystalline nature analyzed from the X-ray diffraction pattern (XRD), in the case of green method average crystallite size is around 13 nm but in the case of chemical methods average crystalline size is around 34 nm was given in Table 1. Functional groups identified by Fourier transform infrared spectroscopy (FT-IR), stability of the nano-materials represented by dynamic light scattering spectroscopy (DLS) analysis. Similar way ZnO NPs was reported by Elahe Darvishi et al., (2019) through the chemical and green method [1]. The synthesized chemical and green methods Zinc Oxide nanoparticles were used to study the catalytic activity towards the environment polluting dye degradation. However, the results concluded that green method synthesized ZnO NPs shows the superior degradation efficiency with lesser time towards Methylene blue (MB) and Rhodamine B (RhB) dyes and possible mechanism of dye degradation given in Fig.1. In similar way Abdullah et al., (2021) reported Basic Blue 9 (BB9), crystal violet (CV), and cresol red (CR) dyes using bio-inspired ZnO nanoparticles [2].

Table 1. ZnO nanoparticles of geometric parameters

NPs

Lattice plane

2 Theta

FWHM value

d-spacing (Å)

Cos(θ)

Crystallite Size(nm)

Green Method ZnO NPs

(100)

31.87

0.58553

2.8051

0.9615

14.74

(002)

34.28

0.51022

2.6142

0.9555

17.03

(101)

36.37

0.60961

4.9354

0.9500

14.33

(102)

47.41

0.86913

1.9155

0.9156

10.43

(110)

56.72

0.70243

1.6211

0.8799

13.43

(103)

62.93

0.92393

1.4763

0.8529

10.53

(112)

67.94

0.78517

1.3780

0.8293

12.75

Average Size = 13.32

NPs

Lattice plane

2 Theta

FWHM value

d-spacing (Å)

Cos(θ)

Crystallite Size(nm)

Chemical Method ZnO NPs

(100)

31.66

0.20695

2.8230

0.9620

41.69

(002)

34.28

0.19972

2.6128

0.9555

43.50

(101)

36.07

0.22354

2.4874

0.9508

39.05

(102)

47.71

0.27798

1.9040

0.9994

32.65

(110)

56.51

0.33284

1.6267

0.8808

28.31

(103)

62.72

0.35193

1.4796

0.8539

27.62

(112)

67.83

0.36127

1.1102

0.7203

27.69

Average Size =34.358

Fig. 1 Photocatalytic activity of ZnO NPs for the degradation of Methylene blue (MB) and Rhodamine B (RhB) dyes under UV light irradiation