Use of Titanium Dioxide in Organic Paints

Turkchem 15 Mar 2018 44 4 dk okuma

TURKCHEM

Summary

Many factors affect organic dyes. These include dye concentration, pH, dissolved oxygen, light source, catalyst concentration, hydrogen peroxide, temperature, and irradiation time. TiO2 nanoparticles combined with dye molecules have been used in low-cost photovoltaic devices since 1991. Dye-sensitized solar cells (DSCs) have been used over the past 10 years to generate electricity from solar energy [1]. This article, as a literature review, addresses several studies in the literature on the use of titanium dioxide in organic dyes.

Introduction

Protecting clean water resources and water sources from pollution makes water treatment technologies (coagulation, adsorption, filtration, etc.) one of the most important topics in recent times [2]. TiO2 is used in many fields such as energy and environment. The reasons for preferring TiO2 include low cost, good stability, non-toxicity, surface modification, and corrosion protection [3, 4]. Metal and non-metal doped TiO2 is utilized to remove a wide range of pollutants in air and water through sunlight [5]. TiO2 in nanometer scale is directly used as a photocatalyst for dye degradation in contaminated water [6]. Bhardwaj et al. worked with titanium dioxide nanotubes in dye-sensitized solar cell applications [7]. In the literature, there are many non-metals. For example, carbon [8], nitrogen [9], fluorine [10], and boron [11]. These non-metals are used in the modification of TiO2 and for photocatalytic activity in the visible light region. Din et al. [12] published improvements in the catalytic activities of silver-doped and titanium dioxide-doped silver-doped zinc oxide. Dyes are among the most important sources of environmental pollution. A significant portion of water pollutants used in the textile industry are azo dyes [13]. Synthetic dyes constitute an important part of our lives. The product range varies from clothing to leather accessories and furniture [14]. The rate of photocatalytic degradation depends significantly on the basic structure of the molecule and the nature of the group attached to the aromatic ring of the dye. Different substituent groups, such as alkyl groups, methyl, nitrate, hydroxyl, and carboxyl groups, as well as groups containing chlorine atoms, affect photocatalytic degradation. Titanium dioxide (TiO2)-graphitic carbon nitride (C3N4) composites have shown significant improvements in photocatalytic activity. This was obtained when compared to pure TiO2 microspheres. In this work, a photocatalytic reaction mechanism was proposed [15]. In the literature, there are many studies on the fundamentals and mechanisms of photocatalytic degradation of organic dyes [16, 17]. Cheng et al. [18] synthesized 3D-TiO2/rGO aerogels using the hydrothermal method. The absorption behavior of TiO2-rGO was tested with oleic acid and Rhodamine B (RhB) at different TiO2 ratios. Santhi and colleagues studied the effect of pH, TiO2 dose, and irradiation time for dye solution degradation [19]. From the findings obtained, maximum degradation efficiency of 96.6% was achieved in 45 minutes using UV/TiO2/O3 application in the minimum time. This work also demonstrated that TiO2 nanoparticles can be used in the water treatment industry. Prof. Dr. Murat Ateş - Department of Chemistry, Faculty of Arts and Sciences, Namık Kemal University Prof. Dr. Yüksel Bayrak - Department of Chemistry, Faculty of Arts and Sciences, Namık Kemal University Ozan Yörük - Ph.D. Student, Department of Chemistry, Faculty of Science, Trakya University

Results

The studies conducted have shown that the optimal catalyst amount is 0.1 g/L. Depending on the initial dye concentration, photo-degradation decreases as the initial dye concentration increases [20]. Consequently, there are many studies in the literature on the use of TiO2 in organic dyes. Photocatalytic degradation is among the most important studies.