Use of Different Natural Products to Control Growth of Titanium Oxide Nanoparticles in Green Solvent Emulsion, Characterization, and Their Photocatalytic Application.

Eneyew Tilahun Bekele,Fedlu Kedir Sabir,Bedasa Abdisa Gonfa,Anastasios Keramidas

doi:10.1155/2021/6626313

Eneyew Tilahun Bekele, Fedlu Kedir Sabir + Show 2 more

Open Access

https://doi.org/10.1155/2021/6626313

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Abstract

Water, one of the crucial and the pillar resources to every living thing, could be polluted day to day by different causes such as expansion in industrialization, rapid increment in population size, the threat of climate, and growth of urbanization. The existence of a number of organic dyes, detergents, and pesticides from industrial effluents could lead to severe diseases and even to the death of human beings. Currently, remediation of those hazardous organic contaminants using semiconductor metal oxide catalysts has received extensive attention in recent years. Among the numerous nanometal oxides, titanium oxide (TiO2) nanoparticles (NPs) have been well known as a significant photocatalytic material due to their suitable physiochemical behaviors such as stability, conductivity, high surface area to volume ratio, structure, and porosity nature at the nanoscale level. TiO2 semiconductor nanoparticles could be synthesized via several physiochemical approaches; among those, the biogenic technique is the most selective one which involves the synthesis of NPs using different templates. Biogenic synthesis of nanoparticles is an environmentally friendly protocol that involves the use of different parts and types of biogenic sources such as bacteria, fungi, yeast, virus, and green plants or the byproducts of their metabolism, which act as both reducing and stabilizing agents. TiO2 NPs obtained via the biogenic method provide a potential application for the degradation of organic dyes and other pollutants in wastewater. This method of synthesis of NPs has been given a great attention by researchers due to their nontoxicity, low cost, environmental friendliness, the usage of green solvents, and simplicity of the process. This review focuses on summarizing the synthesis of TiO2 NPs using various biogenic sources, characterization, and their photocatalytic applications for the degradation of different wastes and organic dyes from polluted water.

Highlights

In the past decade, there has been a marked increase in the field of synthesis of various nanoparticles such as metallic, metal oxide, nanocomposite, and decorated nanoparticles with controlled morphologies and remarkable features, making them an extensive area of research. e possibility of synthesizing NPs with controlled particle size, shape, and crystalline nature enables NPs to be used for various potential applications, such as degradation of organic pollutants in wastewater, biomedical, biosensor, catalyst for bacterial biotoxin elimination, and for the photoanode in dye-sensitized solar cells (DSSCs) [1,2,3]
Among the various adapted techniques for the synthesis of nanoparticles, biogenic synthesis of nanoparticles is an environmentally friendly protocol that involves the use of different parts and types of biogenic natural sources such as bacteria, fungi, yeast, virus, and different parts of green plants or the byproducts of their metabolism, which act as both reducing and stabilizing agents to prevent the overall growth of nanoparticles during their synthesis process
In our previous work [49], we have reported on the synthesis of TiO2 NPs using titanium tetrabutoxide as a precursor in the presence of ethanolic root extract of Kniphofia foliosa as a template. e obtained XRD analysis shows the average crystalline size was estimated between 8.2 and 10.2 nm for the different volume ratios, and the field-emission scanning electron microscopy (FESEM) result shows the obtained nanoparticles have spherical morphology

Summary

Introduction

There has been a marked increase in the field of synthesis of various nanoparticles such as metallic, metal oxide, nanocomposite, and decorated nanoparticles with controlled morphologies and remarkable features, making them an extensive area of research. e possibility of synthesizing NPs with controlled particle size, shape, and crystalline nature enables NPs to be used for various potential applications, such as degradation of organic pollutants in wastewater, biomedical, biosensor, catalyst for bacterial biotoxin elimination, and for the photoanode in dye-sensitized solar cells (DSSCs) [1,2,3]. Most organic dyes, detergents, and pesticide compounds ordinarily contain benzene and naphthalene rings that cannot be decomposed by conventional physical, biological, and chemical methods Among these protocols from advanced oxidation processes, heterogeneous photocatalysis assisted by semiconductor nanometal oxides such as TiO2 has been suggested as a design which is simple, operates under ambient conditions, has high stability, and cost effective, energy efficient, and environmentally safe. Green synthesis of nanomaterials is getting increased attention because of its simplicity, fastness, ecofriendliness, and nontoxic nature, and it involves the use of green solvents such as distilled water and ethanol and an economical approach [1,2,3] It involves three important steps during the synthesis process such as solvent medium selection, environmental benign reducing and capping agent selection, and nontoxic substances for nanoparticles stability selection [20,21,22]. High-surface-area (smallsized) NPs of titanium oxides are highly recommended for photocatalytic degradation of dye pollutants in waste water [32,33,34,35]

Biogenic Synthesis Methods of Titanium Oxide Nanoparticles

Characterization Techniques Used for Bioassisted Synthesized TiO2 NPs

Photocatalytic Applications of Biogenic Synthesized TiO2 NPs

Conclusions

Future Perspectives

Disclosure