Preface

Chapter 24 **Investigation of Optical Properties and Radiation Stability of**

**of Various Oxides 485**

**VIII** Contents

and Alexey N. Sokolovskiy

**TiO2 Powders before and after Modification by Nanopowders**

Mikhail M. Mikhailov, Vitaly V. Neshchimenko, Semyon A. Yuryev

Titanium dioxide is currently being used in many industrial products. It provides unique photocatalytic properties for water splitting and purification, bacterial inactivation, and or‐ ganic degradation. In addition, due to its desirable optical, electronic, and mechanical prop‐ erties, it has been widely used as the photoanode for dye-sensitized solar cells (DSSCs) and coatings for self-cleaning surfaces, biomedical implant, and nanomedicine. This book covers various aspects of titanium dioxide nanomaterials including their unique one-dimensional, two-dimensional, mesoporous, and hierarchical nanostructures and their synthetic methods such as sol-gel, hydrothermal, anodic oxidation, and electrophoretic deposition (EPD), as well as its key applications. Through these 24 chapters written by experts from the interna‐ tional scientific community, readers will have access to a comprehensive overview of the recent research and development findings on the titanium dioxide nanomaterials through original research studies and literature reviews. Chapter 1 provides a comprehensive over‐ view on the preparation of titanium dioxide hierarchical nanostructures (HNSs) by various synthetic routes and summarizes the merits and demerits of those synthetic techniques. It also linked the applications of HNSs to the morphologies obtained from different synthetic techniques. Chapter 2 presents a one-step surface hydrolysis method to prepare high-aspect ratio TiO2 nanoflakes, which shows enhanced photocatalytic activities for the degradation of methylene blue, better rate capabilities and excellent cycling stability as a negative electrode material for Li-ion batteries, and improved photon energy conversion efficiency in the DSSCs. Chapter 3 provides detailed experimental conditions for the preparation of mesopo‐ rous TiO2 films and their physicochemical characteristics, as well as their photocatalytic ap‐ plications. Chapter 4 reveals the effects of deposition parameters on the characteristics of the TiO2 and doped TiO2 thin films by sol-gel process, and it has been found that dopants were able to improve the mechanical, optical, and surface properties of TiO2 thin films. Chapter 5 reports the nonaqueous solvent sol-gel route for the synthesis of metal ion (Zr+4 or Na+ )-dop‐ ed TiO2 with improved photocatalytic properties due to small grain size, reduced electron hole recombination, and formation of oxygen vacancies in the TiO2 structures. Chapter 6 in‐ vestigates the effect of various electrochemical parameters such as applied voltage, anodiza‐ tion time, and electrolyte composition on the formation of TiO2 nanotube arrays (TNAs) in aqueous and organic electrolytes by anodic oxidation. Chapter 7 presents the one-step and two-step anodic oxidation processes for making one-dimensional TiO2 nanotube/nanowire arrays with various unique morphologies. It reveals the formation mechanisms through in‐ vestigating several key synthetic process parameters and characterizes the photocatalytic and photoelectrochemical activities of these nanostructures through the degradation of methylene blue. Chapter 8 presents an overview on the different methods used for the prep‐ aration of titanium dioxide nanomaterials including nanoparticles. Chapter 9 investigates

the influence of the stabilizing agents on electrophoretic deposition of TiO2, and it reveals the importance of monitoring and controlling zeta potential during the EPD process. Chap‐ ter 10 presents an original work on the characterization of the optical property of nanostruc‐ tured TiO2 by X-ray absorption near-edge structure (XANES) and X-ray-excited optical luminescence (XEOL). It demonstrates that the combined XANES-XEOL is an effective prob‐ ing technique to reveal the relationship between nanostructures and optical properties of TiO2 nanotubes with element specificity. Chapter 11 presents the use of the CVD process to deposit anatase-TiO2 thin films of different grain size and thickness and evaluate their pho‐ tocatalytic efficiency for the degradation of methyl orange dye under UV light irradiation. Chapter 12 provides an overview on the structure, properties, and synthesis of blue titanium dioxide, which has reduced bandgap energy, thereafter allowing better utilization of a wide region of solar light irradiant energy. Chapter 13 presents an original research work on us‐ ing UV-TiO2 and UV-TiO2-H2O2 systems to photocatalytically degrade five selected organo‐ phosphorus pesticides. Chapter 14 reports the use of digital inkjet printing method to deposit TiO2 photocatalyst films on porcelain grès, which exhibits superior photocatalytic performance for the removal of volatile organic compounds (VOCs) and NOx from air. Chapter 15 presents an excellent, original work on the preparation, characterization, and performance evaluation of TiO2-layered double hydroxides (LDHs) for phenol photodegra‐ dation. Chapter 16 presents the synthesis of visible light-driven photocatalysis that uses het‐ erostructures obtained by combining low bandgap semiconductors with TiO2. Through analysis, the photocatalytic performance of TiO2-based heterostructures for the degradation of organic pollutants in water using visible light and sunlight explores the mechanisms lead‐ ing to the increase of photocatalytic activities of such heterostructures. Chapter 17 presents a comprehensive overview on the fabrication and characterization of silver nanoparticles that incorporated TiO2 and its photocatalytic performance for bacterial inactivation and dye deg‐ radation. It reveals the effect of fabrication methods, pH, light intensity, dose of photocata‐ lyst, UV, and visible light intensity on the performance of the TiO2-Ag nanoparticles. Chapter 18 gives an overview on the synthesis of titanium dioxide nanostructures and the advantages of using nanostructures of titanium dioxide in dye-sensitized solar cell. Chapter 19 presents good strategies for bandgap engineering of one-dimensional TiO2 to improve its optical properties, charge carrier separation, and transfer. It also gives examples of using 1D TiO2 nanostructures in photocatalytic water splitting and dye-sensitized solar cells. Chapter 20 presents a comprehensive overview on various approaches used to modify TiO2 material for dye-sensitized solar cells to enhance their electronic mobility, charge carrier generation and diffusion, conduction band shift, surface passivation, light harvesting, and long-term stability. Chapter 21 presents an overview on various surface treatments/coatings of titani‐ um dioxide particles in order to satisfy different performance requirements in various appli‐ cations such as paints and coatings, printing inks, plastics, and paper. Chapter 22 presents the synthesis of nanostructured titanium dioxides by hydro-/solvothermal-seeded technique and investigates its application as the photoanode for dye-sensitized solar cells, as photoca‐ talysts for self-cleaning films on textiles, antibacterial coating on cotton, and antifouling coating on wood. Chapter 23 presents an overview on the applications of TiO2 nanotube ar‐ rays (TNAs) for biomedical implants, nanomedicine in therapy, nanodiagnostics, and nanobiosensors and explains the mechanism of cell-TNA interactions, which is important for developing novel or improved nanomaterial products for medicine and health applications. Chapter 24 reports the optical properties and radiation stability of titanium dioxide powders

after modification with nanoparticles of various other oxides. It reveals reasons that influ‐

This publication provides a comprehensive overview of current efforts on the synthesis and characterization of titanium dioxide nanomaterials mainly for environmental and energy applications. It will be useful for researchers and students who work in the areas of nanoma‐ terials and green technologies. I gratefully acknowledge all the chapter authors for their en‐ thusiastic and collaborative contributions, and I would like to thank Ms. Marijana Francetic, Author Service Manager, for her guidance and support in the preparation of this book.

> **Dongfang Yang, PhD** Senior Research Officer

Preface XI

London, Ontario, Canada

Automotive and Surface Transportation National Research Council Canada

ence the radiation stability and methods to improve such stability.

after modification with nanoparticles of various other oxides. It reveals reasons that influ‐ ence the radiation stability and methods to improve such stability.

the influence of the stabilizing agents on electrophoretic deposition of TiO2, and it reveals the importance of monitoring and controlling zeta potential during the EPD process. Chap‐ ter 10 presents an original work on the characterization of the optical property of nanostruc‐ tured TiO2 by X-ray absorption near-edge structure (XANES) and X-ray-excited optical luminescence (XEOL). It demonstrates that the combined XANES-XEOL is an effective prob‐ ing technique to reveal the relationship between nanostructures and optical properties of TiO2 nanotubes with element specificity. Chapter 11 presents the use of the CVD process to deposit anatase-TiO2 thin films of different grain size and thickness and evaluate their pho‐ tocatalytic efficiency for the degradation of methyl orange dye under UV light irradiation. Chapter 12 provides an overview on the structure, properties, and synthesis of blue titanium dioxide, which has reduced bandgap energy, thereafter allowing better utilization of a wide region of solar light irradiant energy. Chapter 13 presents an original research work on us‐ ing UV-TiO2 and UV-TiO2-H2O2 systems to photocatalytically degrade five selected organo‐ phosphorus pesticides. Chapter 14 reports the use of digital inkjet printing method to deposit TiO2 photocatalyst films on porcelain grès, which exhibits superior photocatalytic performance for the removal of volatile organic compounds (VOCs) and NOx from air. Chapter 15 presents an excellent, original work on the preparation, characterization, and performance evaluation of TiO2-layered double hydroxides (LDHs) for phenol photodegra‐ dation. Chapter 16 presents the synthesis of visible light-driven photocatalysis that uses het‐ erostructures obtained by combining low bandgap semiconductors with TiO2. Through analysis, the photocatalytic performance of TiO2-based heterostructures for the degradation of organic pollutants in water using visible light and sunlight explores the mechanisms lead‐ ing to the increase of photocatalytic activities of such heterostructures. Chapter 17 presents a comprehensive overview on the fabrication and characterization of silver nanoparticles that incorporated TiO2 and its photocatalytic performance for bacterial inactivation and dye deg‐ radation. It reveals the effect of fabrication methods, pH, light intensity, dose of photocata‐ lyst, UV, and visible light intensity on the performance of the TiO2-Ag nanoparticles. Chapter 18 gives an overview on the synthesis of titanium dioxide nanostructures and the advantages of using nanostructures of titanium dioxide in dye-sensitized solar cell. Chapter 19 presents good strategies for bandgap engineering of one-dimensional TiO2 to improve its optical properties, charge carrier separation, and transfer. It also gives examples of using 1D TiO2 nanostructures in photocatalytic water splitting and dye-sensitized solar cells. Chapter 20 presents a comprehensive overview on various approaches used to modify TiO2 material for dye-sensitized solar cells to enhance their electronic mobility, charge carrier generation and diffusion, conduction band shift, surface passivation, light harvesting, and long-term stability. Chapter 21 presents an overview on various surface treatments/coatings of titani‐ um dioxide particles in order to satisfy different performance requirements in various appli‐ cations such as paints and coatings, printing inks, plastics, and paper. Chapter 22 presents the synthesis of nanostructured titanium dioxides by hydro-/solvothermal-seeded technique and investigates its application as the photoanode for dye-sensitized solar cells, as photoca‐ talysts for self-cleaning films on textiles, antibacterial coating on cotton, and antifouling coating on wood. Chapter 23 presents an overview on the applications of TiO2 nanotube ar‐ rays (TNAs) for biomedical implants, nanomedicine in therapy, nanodiagnostics, and nanobiosensors and explains the mechanism of cell-TNA interactions, which is important for developing novel or improved nanomaterial products for medicine and health applications. Chapter 24 reports the optical properties and radiation stability of titanium dioxide powders

X Preface

This publication provides a comprehensive overview of current efforts on the synthesis and characterization of titanium dioxide nanomaterials mainly for environmental and energy applications. It will be useful for researchers and students who work in the areas of nanoma‐ terials and green technologies. I gratefully acknowledge all the chapter authors for their en‐ thusiastic and collaborative contributions, and I would like to thank Ms. Marijana Francetic, Author Service Manager, for her guidance and support in the preparation of this book.

#### **Dongfang Yang, PhD**

Senior Research Officer Automotive and Surface Transportation National Research Council Canada London, Ontario, Canada

**Section 1**

**Synthesis and Characterization**

**Synthesis and Characterization**

**Chapter 1**

**Provisional chapter**

HNSs

, Titania, microwave

**Hierarchical Nanostructures of Titanium Dioxide:**

**Hierarchical Nanostructures of Titanium Dioxide:** 

DOI: 10.5772/intechopen.74525

This chapter covers different routes of preparation of hierarchical nanostructures (HNS) of titanium dioxide. Keeping the interest in developing modern and sustainable methods of materials chemistry, this chapter focuses on synthesis routes for TiO<sup>2</sup>

reported by researchers from all over the world. The chapter includes the details of chemical reactions taking place during the synthesis and the effects of various process parameters like: type of surfactants, organic/inorganic titanium salts, temperature and

sequently compared in terms of their morphology, crystallite size, surface area, particle size and phase. The merits and demerits of all synthesis techniques are also added for comprehensive information. At the end, various applications of HNSs are discussed and their performance is analyzed with respect to the morphologies obtained from different

**Keywords:** hierarchical nanostructures (HNSs), nanoflowers, TiO<sup>2</sup>

HNSs from different synthesis routes are sub-

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

distribution, and reproduction in any medium, provided the original work is properly cited.

and reproduction in any medium, provided the original work is properly cited.

Depletion of fossil fuels and environmental pollution has reached an alarming situation. New techniques are being searched now to overcome this situation by switching toward sustainable and renewable energy resources [1–4]. Severe pollution threats like global warming demand such materials and devices that are environment-friendly and green. The main idea is to fabricate materials that are not only cost-effective [5] but are also more capable to deal

**Synthesis and Applications**

**Synthesis and Applications**

http://dx.doi.org/10.5772/intechopen.74525

**Abstract**

Ramsha Khan, Sofia Javed and Mohammad Islam

Ramsha Khan, Sofia Javed and Mohammad Islam

Additional information is available at the end of the chapter

Additional information is available at the end of the chapter

pressure on products. The obtained TiO<sup>2</sup>

synthesis techniques.

with energy crisis in the world.

synthesis

**1. Introduction**

#### **Hierarchical Nanostructures of Titanium Dioxide: Synthesis and Applications Hierarchical Nanostructures of Titanium Dioxide: Synthesis and Applications**

DOI: 10.5772/intechopen.74525

Ramsha Khan, Sofia Javed and Mohammad Islam Ramsha Khan, Sofia Javed and Mohammad Islam

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.74525

#### **Abstract**

This chapter covers different routes of preparation of hierarchical nanostructures (HNS) of titanium dioxide. Keeping the interest in developing modern and sustainable methods of materials chemistry, this chapter focuses on synthesis routes for TiO<sup>2</sup> HNSs reported by researchers from all over the world. The chapter includes the details of chemical reactions taking place during the synthesis and the effects of various process parameters like: type of surfactants, organic/inorganic titanium salts, temperature and pressure on products. The obtained TiO<sup>2</sup> HNSs from different synthesis routes are subsequently compared in terms of their morphology, crystallite size, surface area, particle size and phase. The merits and demerits of all synthesis techniques are also added for comprehensive information. At the end, various applications of HNSs are discussed and their performance is analyzed with respect to the morphologies obtained from different synthesis techniques.

**Keywords:** hierarchical nanostructures (HNSs), nanoflowers, TiO<sup>2</sup> , Titania, microwave synthesis
