Characterization Of Titanium Dioxide Nanoparticles Research Articles

Green Synthesis and Characterization of Titanium Dioxide Nanoparticles by Aspergillus niger DS22 and Its Potential Application in Medical Fields

Green Synthesis and Characterization of Titanium Dioxide Nanoparticles by Aspergillus niger DS22 and Its Potential Application in Medical Fields

Synthesis and characterization of titanium dioxide nanoparticles from Bacillus subtilis MTCC 8322 and its application for the removal of methylene blue and orange G dyes under UV light and visible light.

Over the last decade there has been a huge increase in the green synthesis of nanoparticles. Moreover, there is a continuous increase in harnessing the potential of microorganisms for the development of efficient and biocompatible nanoparticles around the globe. In the present research work, investigators have synthesized TiO2 NPs by harnessing the potential of Bacillus subtilis MTCC 8322 (Gram-positive) bacteria. The formation and confirmation of the TiO2 NPs synthesized by bacteria were carried out by using UV-Vis spectroscopy, Fourier transforms infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), and energy dispersive X-ray spectroscopy (EDX/EDS). The size of the synthesized TiO2 NPs was 80-120nm which was spherical to irregular in shape as revealed by SEM. FTIR showed the characteristic bands of Ti-O in the range of 400-550cm-1 and 924cm-1 while the band at 2930cm-1 confirmed the association of bacterial biomolecules with the synthesized TiO2 NPs. XRD showed two major peaks; 27.5° (rutile phase) and 45.6° (anatase phase) for the synthesized TiO2 NPs. Finally, the potential of the synthesized TiO2 NPs was assessed as an antibacterial agent and photocatalyst. The remediation of Methylene blue (MB) and Orange G (OG) dyes was carried out under UV- light and visible light for a contact time of 150-240min respectively. The removal efficiency for 100ppmMB dye was 25.75% and for OG dye was 72.24% under UV light, while in visible light, the maximum removal percentage for MB and OG dye was 98.85% and 80.43% respectively at 90min. Moreover, a kinetic study and adsorption isotherm study were carried out for the removal of both dyes, where the pseudo-first-order for MB dye is 263.269 and 475554.176mg/g for OG dye. The pseudo-second-order kinetics for MB and OG dye were 188.679 and 1666.667mg/g respectively. In addition to this, the antibacterial activity of TiO2 NPs was assessed against Bacillus subtilis MTCC 8322 (Gram-positive) and Escherichia coli MTCC 8933 (Gram-negative) where the maximum zone of inhibition in Bacillus subtilis MTCC 8322 was about 12mm, and for E. coli 16mm.

Characterization of titanium dioxide nanoparticles in confectionary products and estimation of dietary exposure level among the Chinese population

Titanium dioxide (TiO2) is widely used in the food industry. Recently, European Commission has banned TiO2 as a food additive, raising public concern about its health risk, especially the nanoparticles (NPs) contained therein. This study aimed to reveal the existence of TiO2 NPs in food and further estimate the dietary exposure level among Chinese population by characterizing particle size distribution, determining Ti content and micro-distribution in food products, and calculating food consumption from the China Health and Nutrition Survey (CHNS). The results showed that TiO2 particle size in food additives and chewing gums was 53.5–230.3 nm and 56.8–267.7 nm respectively, where NPs accounted for 34.7% and 55.6% respectively. TiO2 was firstly in situ presented on the surface of confectionary products with hard shells. The content of TiO2 ranged from 3.2 to 3409.3 μg/g product. Besides, the mean dietary intake was 71.31 μg/kgbw/day for TiO2 and 7.75 μg/kgbw/day for TiO2 NPs among Chinese population, affected by people's dietary habits of different regions. Children's exposure levels was the highest due to their love of sweets. More attention should be paid to risk assessment and management of TiO2 NPs for children in China.

Facile Characterization of Titanium Dioxide Nano- particles Prepared via Hydrothermal Method with in-situ Surface Modification

Aim: The present study is focused on the synthesis and characterization of titanium dioxide nanoparticles prepared via the hydrothermal method prepared via in-situ surface modification. 
 Purpose of the study: The proposed research is based on the requirement of alternate antimicrobial therapies. The global misuse and overuse of antibiotics have given rise to the antibiotic resistance crisis. The emergence of multi-drug resistant bacteria has failed the conventional treatment methods involving antibiotics. To meet the need for efficient alternate strategies, metal oxide nanoparticles such as titanium dioxide are explored since it's known for their preventing and treating infections.
 Method: Titanium dioxide nanoparticles were successfully synthesized via hydrothermal and Surface modification of nanoparticles in dehydrated ethanol at room temperature. The obtained nanoparticles are characterized by utilizing Scanning Electron Microscope, Transmission Electron Microscope, Energy Dispersive X-ray Spectroscopy, Zeta Potential Analysis, Thermogravimetric analysis, and Fourier transform Infrared spectroscopy. 
 Results: According to scanning electron microscopy and transmission electron microscopy, the morphological analysis of the synthesized titanium dioxide was spherical shaped and had an average size of 5-20nm and a size distribution of 14-20nm. The Energy Dispersive X-ray spectroscopy analysis depicted the percentage of elements in TiO2 as Ti (47.10%) and O2 (52.90%). The zeta potential for titanium dioxide was reported as -13.39, and the negative value indicated superior physical stability of nanoparticles in a suspension. The Fourier Transform Infrared spectroscopy peak at 1417.68 indicated the O-Ti-O bond in anatase morphology. While Thermogravimetric analysis showed three main stages of mass loss, there was no mass loss after 503°C, which started oxide formation.
 Conclusion: It was concluded from the present study that the synthesis of titanium dioxide is an economical process and yields excellent nanoparticles via the hydrothermal method. Characterization of the nanomaterial allowed us to determine the thermal stability, morphology, and purity of titanium dioxide nanoparticles.

Biogenic Photo-Catalyst TiO2 Nanoparticles for Remediation of Environment Pollutants.

This article reports a benign environmentally friendly fabrication method of titanium dioxide (TDO) nanoparticles (named TDO NPs3, TDO NPs5, and TDO NPs8) using aqueous extract of durva herb waste. This synthesis process avoids use of harmful substances and persistent chemicals throughout the order and enables us to control the size of the nanomaterials. Characterization of TDO nanoparticles was analyzed by ultraviolet–visible spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The morphological nature of the TDO samples was inspected by transmission electron microscopy, which indicated that the TDO NPs3, TDO NPs5, and TDO NPs8 were spherical in shape, with average sizes of 5.14, 12.54, and 29.61 nm, respectively. The stability of TDO nanoparticles was assessed using thermogravimetric analysis and dynamic light scattering analysis. These samples could be used for degradation of polluting industrial textile dyes, such as methylene blue (MB) and rhodamine B (Rh-B). Remarkably, the TDO NPs3 sample (5.14 nm size) exhibits a noticeable degradation of the MB dye in a shorter time period (50 min) than the TDO NPs8 sample with a size of 29.61 nm (120 min). The TDO NPs3 sample was also tested for degradation of Rh-B dye, showing high degradation efficiency over a short period of time (60 min). In contrast, the TDO NPs8 sample showed degradation of the Rh-B dye in 120 min. The effect of the dye concentration and the catalyst dose to remove dye pollutants has also been investigated. The synthesized TDO NPs act as exceptional catalysts for the degradation of dyes, and they are promising materials for the degradation of industrial polluting dyes.

Facile Green Synthesis and Characterization of Titanium Dioxide Nanoparticles Using Kigelia africana (Lam) Benth., Aqueous Leaf Extract and its Antioxidant and Antibacterial Activity

Titanium nanoparticles are toxic to bacteria and have a widespread applications in different fields of research. Hence the present study aimed to synthesize the titanium dioxide nanoparticles by adopting green synthesis methodology using Kigelia africana leave extract as a biological reducing agent. The UV absorption spectra show characteristic absorption maxima corresponding to TiO2 nanoparticles at a wavelength of 512 nm confirms the formation of nanosized tin particles. The FT-IR spectrum of TiO2 nanoparticles show absorption bands at 3609 cm-1 and 3227 cm-1 corresponding to O-H stretching in alcoholic and carboxylic compounds, respectively. Absorption peaks at 1607, 2834, 1654 and 1324 cm-1 correspond to aromatic C=C vibrations, C-H stretching in aldehydes, C-H bending vibrations and aromatic C-N stretching vibrations, respectively. This confirms the involvement of bioactive compounds from the plant extract. The SEM and EDX studies confirmed that the nanoparticles are spherical to oval shape with an average particle size of 46 nm. The metal content in the nanoparticles was found to be 58.71%. The synthesized nanoparticles have potential growth inhibition activity against Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli). The DPPH radical scavenging activity of the nanoparticles synthesized was compared with that of aqueous leaf extract and standard ascorbic acid and proved that the nanoparticles have enhanced activity than aqueous leaf extract. The IC50 of the leaf extract, nanoparticles and the standard was found to be 31.55, 75.82 and 84.95 μg/mL, respectively. Kigelia africana leaf is shown in this work to be a valuable bioagent in the biosynthesis of TiO2 nanoparticles with increased biological activity.

Biosynthesis and characterization of titanium dioxide nanoparticles and its effects along with calcium phosphate on physicochemical attributes of wheat under drought stress

Drought stress is reducing the production of crops globally. This research was designed to evaluate the role of titanium dioxide (TiO2 NPs) nanoparticles and calcium phosphate on wheat facing drought stress. TiO2 NPs were prepared by green synthesis and their characterization (by UV–visible spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX)) was also done. The results showed that TiO2 NPs worked efficiently and improved plant growth under drought. However, the best results were obtained from combined applications of 40 ppm TiO2 NPs and 40 ppm calcium phosphate on plants. They increased root length (33%), shoot length (53%), fresh weight (48%), and dry weight (44%) of wheat as compared to control. The physiological parameters including chlorophyll content, relative water content, membrane stability index, and osmolyte content (proline and sugar) were also improved. The increase in superoxide dismutase, peroxidase and, catalase activity by the combined application of TiO2 NPs and calcium phosphate was 83% and 78%, 74% and 52%, 81%, and 67% in Pakistan-13 and Zincol-16 respectively, as compared to untreated drought exposed plants. They also enhanced the nutrients uptake (including potassium, phosphorus, and nitrogen) that ultimately improved plant biomass. They also maintained the level of growth hormones in plants. These hormones regulate cellular processes and are responsible for germination, development, and plant reaction in drought stress. The increase in the yield was also significant, hence it is recommended that the 40 ppm concentration of TiO2 NPs along with calcium phosphate improves the productivity of wheat under drought stress.

Green synthesis and characterization of titanium dioxide nanoparticles using leaf extract of Pouteria campechiana and larvicidal and pupicidal activity on Aedes aegypti

The frequent application of synthetic insecticides creates resistance among insects, including mosquitoes, and causes environmental pollution and health issues. The current work aim at assessing the possibilities to produce and characterize the titanium dioxide (TiO2) nanoparticles (TiO2 NPs) mediated through the aqueous leaf extract of Pouteria campechiana, and their larvicidal and pupicidal activities against Aedes aegypti. The attained results showed that the aqueous leaf extract of P. campechiana had the efficiency to fabricate TiO2 NPs from TiO2. Under the UV-vis spectrum analysis, a sharp peak was recorded at 320 nm, which indicated the production of TiO2 NPs by the plant extract. The SEM analysis revealed that the synthesized TiO2 NPs were spherical, and 5 dissimilar diffractions were detected in the XRD spectrum analysis related to the TiO2 NPs. In FTIR analysis, a prominent peak was found at 1052.41 cm−1, corresponding to alcohol, and confirmed metal reduction. In the EDX analysis, there was a signal of around 58.44%, confirming the decrease in Ti from TiO2 NPs, and the remaining percentages were Ca, Al, and Mg. About 900 μg mL−1 of TiO2 NPs had excellent lethal activity against various larvae and pupa stages of Ae. aegypti. The attained results showed that the P. campechiana aqueous leaf extract could reduce TiO2 into TiO2 NPs and could be considered a mosquito control agent. Furthermore, this is the initial report about the aqueous leaf extract of P. campechiana effectively synthesizing the TiO2 NPs with anti-mosquito activity.

First principles characterisation of bio-nano interface.

Nanomaterials possess a wide range of potential applications due to their novel properties and exceptionally high activity as a result of their large surface to volume ratios compared to bulk matter. The active surface may present both advantage and risk when the nanomaterials interact with living organisms. As the overall biological impact of nanomaterials is triggered and mediated by interactions at the bio-nano interface, an ability to predict those from the atomistic descriptors, especially before the material is produced, can present enormous advantage for the development of nanotechnology. Fast screening of nanomaterials and their variations for specific biological effects can be enabled using computational materials modelling. The challenge lies in the range of scales that needs to be crossed from the material-specific atomistic representation to the relevant length scales covering typical biomolecules (proteins and lipids). In this work, we present a systematic multiscale approach that allows one to evaluate crucial interactions at the bionano interface from the first principles without any prior information about the material and thus establish links between the details of the nanomaterials structure to protein-nanoparticle interactions. As an example, an advanced computational characterization of titanium dioxide nanoparticles (6 different surfaces of rutile and anatase polymorphs) has been performed. We computed characteristics of the titanium dioxide interface with water using density functional theory for electronic density, used these parameters to derive an atomistic force field, and calculated adsorption energies for essential biomolecules on the surface of titania nanoparticles via direct atomistic simulations and coarse-grained molecular dynamics. Hydration energies, as well as adsorption energies for a set of 40 blood proteins are reported.

Preparation and characterization of titanium dioxide nanoparticles and in vitro investigation of their cytotoxicity and antibacterial activity against Staphylococcus aureus and Escherichia coli

Titanium dioxide nanoparticles (TiO2 NPs) are photo-active metallic nanoparticles becoming promising agents in modern biomedical applications. Herein, a novel process for the synthesis of TiO2 NPs with high stability was developed by a sol–gel process and to investigate their cytotoxicity and antibacterial activity. Numerous experiments have been performed to confirm the morphologies, compositions, and physicochemical properties of prepared TiO2 NPs, such as field emission scanning electron microscopy, dynamic light scattering, Zeta potential, Fourier transform infrared spectroscopy and X-ray diffraction. MTT assay was applied to assess the cytotoxicity of the prepared nanoparticles. The results indicate that the synthesized nanoparticles' diameter is about 68 nm and contains the anatase phase, in the range of 2θ from 25 to 80 °C. The hydrodynamic radius of nanoparticles is about 140.4 nm, and the zeta potential of nanoparticles is about −44.6 mV. The MTT results have not shown any toxicity; the antibacterial inhibitory effect of TiO2 NPs at 200 mg/mL concentrations exhibited superior antibacterial activity at 15.9 ± 0.1, 14.0 ± 0.1 against Staphylococcus aureus and Escherichia coli, respectively. In conclusion, colloidal solutions with high stability were successfully synthesized, contributing to decreased dimensions and increased antibacterial properties.

An innovative filtration based Raman mapping technique for the size characterization of anatase titanium dioxide nanoparticles

Characterization of titanium dioxide nanoparticles (TiO2-NPs) is of significant importance in the production quality control, applications and study of their toxicological effects. In this study, we developed a filtration-based Raman mapping technique as a rapid approach for the analysis of different sizes and concentrations of anatase TiO2-NPs. Four different sizes of TiO2 standards: 173, 93, 41, and 8 nm measured by electron microscopy techniques were dispersed using a probe sonicator with sodium pyrophosphate as a dispersing agent. The resulting hydrodynamic diameter measured by dynamic light scattering (DLS) was stabilized at 192, 289, 325, and 360 nm respectively as a negative correlation with the ones by TEM. These NPs were then collected on a 0.1 μm (pore size) filter membrane with a vacuum pump and scanned using a Raman imaging microscope. The result shows that the 100 × objective lens was more capable of detecting the smallest size particles (8 nm) and lowest concentration (0.0004 g L−1) evaluated than the 20 × objective lens. Moreover, at low concentrations (i.e. 0.0004 and 0.004 g L−1), we established a linear correlation between the map area covered by the particles and the particle size measured by TEM. While at higher concentration (i.e. 0.04 g L−1), a positive correlation was established between the particle size and its corresponding Raman intensity. These results demonstrated a successful application of Raman mapping technique in rapid characterization of the size of anatase TiO2-NPs as small as 8 nm, which will facilaite the TiO2-NPs research, production, and applications.

Synthesis and characterization of titanium dioxide nanoparticles by chemical and green methods and their antifungal activities against wheat rust

The production of metallic nanoparticles (NPs) by green and ecofriendly methods has received consideration during the recent past. The present study summarized the comparative production of titanium dioxide (TiO2) NPs by plant extracts of Trianthema portulacastrum (T2) and Chenopodium quinoa (T3) and by conventional chemical (sol-gel) method (T1). Synthesized TiO2-NPs were examined by high-tech. techniques such as X-Ray Diffraction (XRD), Fourier Transmission Infra-red (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray (EDX) spectroscope, SEM-EDS spot analysis and elemental mapping. Synthesized TiO2-NPs were applied on wheat rust (Ustilago tritici) for the evaluation of their antifungal activity against toxic plant pathogens. XRD results confirmed the (2θ) peak at 25.3 related to 101 anatase form. EDS-spot analysis and elemental mapping confirms the formation of TiO2-NPs by using these techniques. SEM secondary electrons (SEs) images demonstrated the nano range of particles in cluster form with fewer porous structures. The average size of all three TiO2-NPs was found less than 15 nm. FT-IR analysis of all three TiO2-NPs perfectly matched with the standard parameters. The NPs prepared by both sol-gel and green methods have a good antifungal response against U. tritici, and the green prepared TiO2-NPs were found to have the best antifungal activity against wheat rust especially NPs synthesized with the extract of C. quinoa. Overall, green method can be used for the large scale and less toxic synthesis of TiO2-NPs because of their wide range of environmental applications.

Adsorption of Sr(II) cations onto phosphated mesoporous titanium dioxide: Mechanism, isotherm and kinetics studies

In this work, phosphate-modified titanium dioxide nanoparticles with mesoporous structure were synthesized and utilised as an efficient nanoadsorbent for Sr(II) removal from aqueous environment. The globular titania particles with a 3–4 nm diameter with chemosorbed on their surfaces phosphate groups = Ti(O2POOH) have been obtained by liquid-phase synthesis. The characterization of titania nanoparticles were performed using XRD, TEM, IR-spectroscopy and Brunauer-Emmett-Teller analyses. The synthesized modified adsorbents exhibited SBET = 396–410 m2 g−1 and mesopore volume of 0.262 – 0.275сm3 g−1. The isotherm and kinetic models were used for the description of Sr(II) adsorption. The sample 4P-TiO2 showed the best adsorption ability for strontium ions removal. The adsorption capacity of Sr(II) onto modified 2P-TiO2, 4P-TiO2 and 8P-TiO2 samples was found to be 94.1, 172.5, 128.9 mg/g, respectively. An adsorption mechanism for Sr(II) removal was proposed. The adsorption/desorption studies were conducted to find the reusability of phosphated adsorbents. A titanium dioxide-based mesoporous material possesses a significant adsorption activity due to high content of surface acid sites. All the outcomes revealed that the phosphate modified titania showed great potential in Sr(II) removal from aqueous environment and nuclear effluents.

Synthesis and Characterization of Titanium Dioxide Nanoparticles with a Dosimetry Study of their Ability to Enhance Radiation Therapy using a Low Energy X-ray Source

Objective: This study was undertaken to synthesize and characterize TiO2 NPs and to study the interaction of TiO2 NPs with radiation and then estimate the Dose-enhancement Factor (DEF) at different concentrations of NPs under low-energy excitation (14-35 kV). Methods: Titanium dioxide (TiO2 ) Nanoparticles (NPs) were synthesized by the sol-gel method. The structure, particle size and crystal phase were evaluated by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD). Findings: The XRD pattern exhibited peaks that were assigned to analyse crystals with particle sizes from 2-10 nm. The X-ray absorption of TiO2 NP solutions and pure water were investigated. Solutions with 0, 3.33, 6.66 and 20% of the TiO2 NPs were used to study the X-ray absorption of the samples and the Dose Enhancement Factor (DEF) is evaluated. The experimental results showed that the X-ray absorption for solutions with 0, 3.33, 6.66 and 20% of the TiO2 NPs increased with increasing concentration for generated beams from 14 kV to 35 kV. Additionally, a Dose-enhancement Factor (DEF) was observed for low-energy beams between 14 kV and 35 kV. TiO2 NPs at very low energies (14-35 kV) able to display significantly enhanced X-ray absorption, resulting in a higher absorbed dose. Application/Improvements: Many scientists have focused on nanoparticles, such as TiO2 NPs, due to their numerous functions that enhance the nature of their antibacterial properties. Cancer is one of the reasons for human mortality. The main concept of cancer radiotherapy is the enhance radiation dose absorption at the targeted site by using high-Z materials. Keywords: Dosimetry, Low Energy Source, Nanoparticles, Radiation Therapy, Titanium Dioxide

Green synthesis and characterization of titanium dioxide nanoparticles (TiO2 NPs) using Sesbania grandiflora and evaluation of toxicity in zebrafish embryos

Green synthesis of nanoparticles is becoming one of the robust techniques, which may be suitable alternatives for chemical and physical methods. This study reports a cost effective and environmental friendly green synthesis of titanium dioxide nanoparticles (TiO2 NPs) using Sesbania grandiflora. The biosynthesized TiO2 NPs were characterized by Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and Transmission Electron Microscopy (TEM), Ultraviolet–visible spectrophotometry (UV–Vis) and X-ray powder diffraction (XRD). FTIR spectrum confirmed the involvement of alkynes, alkanes, flavonoids and secondary alcohols in the capping and reduction of TiO2 NPs while XRD characterized the crystallographic plane of the rutile phase of TiO2. Size of TiO2 NPs was in the range of 43–56 nm and EDX showed a strong TiO2 signal. The phytosynthesised TiO2 NPs were used for zebrafish embryo toxicity tests, which were performed to monitor the changes in the toxicological effects. Besides, the model adapted in this study was suitable to explore the toxicity in Zebrafish. TiO2 NPs increased bioavailability and uptake into cells and organisms. In order to assess the TiO2 NPs toxic level we employed the fish model as aquatic environment. This study demonstrates that TiO2 NPs are lethal to zebrafish.

Synthesis and Characterization of Titanium Dioxide Nanoparticles for Application in Enhanced Oil Recovery

In this study, titanium dioxide nanoparticles were synthesized for possible application in enhanced oil recovery. Sol-gel method was employed with titanium (IV) isopropoxide as the precursor. The prepared materials were characterized using Powder X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), High-Resolution Transmission electron microscopy (HRTEM) and Brunauer–Emmet–Teller (BET) techniques. Reaction parameter such as calcination temperature was varied during the preparation to obtain the uniform TiO2 nanoparticles with the smallest particle size and high surface area. The results of study revealed that 400 °C is the optimum calcination temperature in preparing TiO2 nanoparticles producing the smallest crystallite and particle sizes. XRD results indicated that the nanoparticles have formed anatase phase at 400 °C and achieved low crystallite size of 7.27 nm with the smallest average particle size of 19.53 nm through FESEM and HRTEM observations. BET analysis had achieved the highest surface area 103.64 m2/g.

Synthesis and Characterization of Titanium Dioxide Nanoparticles under Different pH Conditions

Ethanol as a solvent, a precursor of titanium isopropoxide and a stabilizer of either hydrochloric acid or ammonium hydroxide was used to prepare a titanium dioxide aqueous solution. The aqueous solutions with different values of pH and the morphology of the resultant reaction of the nanoparticles of titanium dioxide were investigated. The X-ray diffraction showed that at low temperatures and with acidic solutions, rutile structures are more favorable to grow on titanium dioxide synthesized, while at low and average temperatures and with base solutions, anatase phase is more pronounced. The crystalline form and the re-confirmation of the crystallite size growth were observed by the scanning electron microscopy. The atomic force microscopy was used to confirm the relation between the roughness and thickness with the pH level.

Synthesis, Physical and Morphological Characterization of Titanium Dioxide Nanoparticles by Wet Chemical Method for Catalytic Applications

TiO2 nanoparticles were synthesized using wet chemical technique and characterized with the help of XRD, SEM, TEM, BET, FT-IR, and UV-Vis analyses. TiO2 samples were studied by XRD to find out their crystal phase as well as its grain size. The prepared amorphous TiO2 nanoparticles were dried first and then sintered at elevated temperatures. Peak intensity of the anatase TiO2 increases with increase in temperature. Higher calcination temperature leads to the formation of a mixture of anatase TiO2 and rutile TiO2. Metal oxide features were observed in FT-IR spectra. SEM analysis was used to examine the surface morphology of the synthesized nanoparticles. TEM studies reveal that the particles are spherical in shape and agglomerated. Specific surface area of the nanocrystals was studied with the help of BET analysis. Photo catalytic activity of the nanoparticles was investigated with the help of UV-Vis spectrophotometer using methylene blue dye and the results are discussed.

Synthesis and characterization of titania nanoparticles and enhancement of photochemical, photoelectrochemical and electrochemical performance with zirconia nanoparticles

Nanosized Zr-doped TiO2 with improved structural stability and photocatalytic properties was synthesized by the sol-gel method. The physicochemical and morphological properties of the catalyst were investigated by transmission electron microscopy, thermogravimetric analysis, differential thermal analysis, X-ray diffraction, and Brunauer-Emmett-Teller analysis. Zr-doped TiO2 possessed a mesoporous structure and a noticeably increased surface area (90 m2 g−1) as compared with pristine TiO2 (28 m2 g−1). On doping with Zr, TiO2 exhibited reinforced texture, improved thermal stability, and enhanced photocatalytic properties. The electrochemical and photoelectrochemical characteristics of the samples were examined by Mott-Schottky analysis and sweep voltammetry under both dark and light conditions.

Characterization of titanium dioxide nanoparticles modified with polyacrylic acid and H2O2 for use as a novel radiosensitizer

An induction of polyacrylic acid-modified titanium dioxide with hydrogen peroxide nanoparticles (PAA-TiO2/H2O2 NPs) to a tumor exerted a therapeutic enhancement of X-ray irradiation in our previous study. To understand the mechanism of the radiosensitizing effect of PAA-TiO2/H2O2 NPs, analytical observations that included DLS, FE-SEM, FT-IR, XAFS, and Raman spectrometry were performed. In addition, highly reactive oxygen species (hROS) which PAA-TiO2/H2O2 NPs produced with X-ray irradiation were quantified by using a chemiluminescence method and a EPR spin-trapping method. We found that PAA-TiO2/H2O2 NPs have almost the same characteristics as PAA-TiO2. Surprisingly, there were no significant differences in hROS generation. However, the existence of H2O2 was confirmed in PAA-TiO2/H2O2 NPs, because spontaneous hROS production was observed w/o X-ray irradiation. In addition, PAA-TiO2/H2O2 NPs had a curious characteristic whereby they absorbed H2O2 molecules and released them gradually into a liquid phase. Based on these results, the H2O2 was continuously released from PAA-TiO2/H2O2 NPs, and then released H2O2 assumed to be functioned indirectly as a radiosensitizing factor.