Addition Of TiO2 Nanoparticles Research Articles

Turbulent forced convective flow in a conical diffuser: Hybrid and single nanofluids

Turbulent forced convective flow of hybrid and single nanofluids in a conical diffuser is investigated numerically. Simulations are conducted for various Reynolds (Re=10000-70000) and different concentrations (ϕ=0-1.5 vol%) at equal ratio of TiO2:SiO2. The impact of using theoretical and experimental correlations for dynamic viscosity and thermal conductivity on turbulent forced convection of TiO2 showed that the mean Nusselt (Nu) number is considerably reduced with the use of the experimental model. However, when the theoretical model is used, Nu varies insignificantly. Addition of TiO2 nanoparticles decreases the heat transfer inside the diffuser, whereas addition of TiO2–SiO2 nanoparticles either enhances or decreases the heat transfer rate. Compared to the pure fluid, hybrid nanofluids show a maximum enhancement of 5% and a maximum decrease of 9.7% at ϕ= 0.5 vol% and ϕ= 0.5 vol% at Re=10000, respectively. However, TiO2 nanofluids show a maximum decrease of 19% at ϕ=1.5 vol% and Re= 30000. As Re increases, the deviations between TiO2 and SiO2-TiO2 nanofluids diminish. Moreover, the Gene Expression Programming model can accurately evaluate Nu versus Re number and nanoparticle concentration.

Experimental study of CO2 capture by nanoparticle-enhanced 2-amino-2-methyl-1-propanol aqueous solution.

2-Amino-2-methyl-1-propanol (AMP) is often used as a moderator to enhance the CO2 capture capacity of absorbents due to its unique spatial site resistance structure, and relatively few studies have been conducted on the enhancement of AMP aqueous solutions by nanoparticles for CO2 capture. In order to investigate the effect of nanoparticles on the CO2 capture performance of AMP aqueous solution, different nanofluids were formulated in this paper using a two-step method, and a bubbling reactor and an oil bath were used as the experimental setup for absorption/desorption, and through comparative experiments, it was found that the type of nanoparticles, the solid content, and the different parameters have great influences on the CO2 absorption load and desorption rate. The experimental results show that the addition of TiO2 nanoparticles to the AMP base solution can accelerate the absorption-desorption mass transfer rate of CO2, and there exists an optimal solid content of 1 g L-1 (±1.0%, ±2.5%); after multiple absorption-desorption experiments, good cycling performance can still be achieved. The experimental results of the nanofluid-promoted mass transfer mechanism are also illustrated and analyzed in this paper.

Antibacterial Effect of Polymethyl Methacrylate Resin Base Containing TiO2 Nanoparticles

Restorations in dentistry must reproduce the aspect of the patient’s natural teeth and require non-toxicity, biocompatibility, and good mechanical properties in order to last longer. Restorations are permanently in contact with microbes that can adhere to and form biofilms. The purpose of this study was to determine the adhesion extent of Streptococcus mutans to polymethyl methacrylate (PMMA) resin base containing TiO2 nanoparticles. To understand the adhesion of Streptococcus mutans on the modified resin-based surfaces, the following surface properties were measured: the roughness, contact angle, zeta potential and CIE color parameters. Evaluation of tensile stress performance in TiO2 modified PMMA showed that the maximum tensile stress of the modified PMMA resin decreases with an increasing amount of TiO2 nanoparticles. The increasing amount of TiO2 decreases the roughness and causes contact angles in the border between hydrophilic and hydrophobic surfaces. All the studied surfaces are negatively charged and added TiO2 tends to increase the zeta potential. The addition of TiO2 nanoparticles increases the lightness and decreases the intensity of the red and yellow color. The increasing addition of TiO2 nanoparticles into PMMA increases the morphological change of bacterial cells.

Roles of nanoparticles in arsenic mobility and microbial community composition in arsenic-enriched soils

Environmental effects of nano remediation engineering of arsenic (As) pollution need to be considered. In this study, the roles of Fe2O3 and TiO2 nanoparticles (NPs) on the microbial mediated As mobilization from As contaminated soil were investigated. The addition of Fe2O3 and TiO2 NPs restrained As(V) release, and stimulated As(III) release. As(V) concentration decreased by 94% and 93% after Fe2O3 addition, and decreased by 89% and 45% after TiO2 addition compared to the Biotic and Biotic+Acetate (amended with sodium acetate) controls, respectively. The maximum values of As(III) were 20.5 and 27.1 µg/L at 48 d after Fe2O3 and TiO2 NPs addition, respectively, and were higher than that in Biotic+Acetate control (12.9 µg/L). The released As co-precipitated with Fe in soils in the presence of Fe2O3 NPs, but adsorbed on TiO2 NPs in the presence of TiO2 NPs. Moreover, the addition of NPs amended with sodium acetate as the electron donor clearly promoted As(V) reduction induced by microbes. The NPs addition changed the relative abundance of soil bacterial community, while Proteobacteria (42.8%-70.4%), Planctomycetes (2.6%-14.3%), and Firmicutes (3.5%-25.4%) were the dominant microorganisms in soils. Several potential As/Fe reducing bacteria were related to Pseudomonas, Geobacter, Desulfuromonas, and Thiobacillus. The addition of Fe2O3 and TiO2 NPs induced to the decrease of arrA gene. The results indicated that the addition of NPs had a negative impact on soil microbial population in a long term. The findings offer a relatively comprehensive assessment of Fe2O3 and TiO2 NPs effects on As mobilization and soil bacterial communities.

Titanium dioxide nanoparticles and elderberry extract incorporated starch based polyvinyl alcohol films as active and intelligent food packaging wraps

Polyvinyl alcohol (P)/starch (S), titanium dioxide nanoparticles (TiO2)/elderberry extract based bionanocomposites (PSTE) were developed by solvent casting method. The developed films were analyzed for morphological, functional, water barrier, mechanical, antimicrobial, food packaging as well as biodegradability studies. Results of the study showed that tensile strength, moisture barrier and antimicrobial properties of the films were significantly improved by the addition of TiO2 nanoparticles. TiO2 nanoparticles were found to be homogeneously dispersed in the polymeric matrix and had good compatibility enabling better functional properties. The elderberry extract addition caused the nanocomposite film a potential pH sensor. Further, the cherry tomato coated with PSTE solution showed reduced weight loss and did not have any sign of microbial infection up to 22 days. Biodegradation studies by soil burial test proved the biodegradability of PSTE bionanocomposites and hence have great promise as active and intelligent food packaging materials.

OPTIMIZATION OF THERMOPHYSICAL PROPERTIES, COMBUSTION PERFORMANCE AND HARMFUL EXHAUST GASES OF BIODIESEL FUEL WITH NANOPARTICLE ADDITIVES

Increasing use of diesel products causes decrease of oil reserves, global warming, increase in the world average and adverse effects on human health and the environment. Emissions from combustion in engines are directly related to the quality, properties and combustion characteristics of the fuel. Since the physical and chemical properties of the fuel affect the atomization characteristics, it is important for increasing the combustion efficiency. The most important fuel properties affecting the combustion of diesel fuel are cetane number, viscosity, density and calorific value. There are many applications in improving the chemical and physical properties of fuel. One of them is nanoparticle (NPs) additives adding in fuel. In this study, it was aimed to improve fuel properties with optimum additive ratio by adding CeO2, TiO2 and Co3O4 nanoparticle additives into biodiesel which are produced from cotton and canola oil. The effects of NPs additives in fuel properties such as viscosity, density, lower calorific value and flash points were investigated.

Effect of Titanium Dioxide Nanoparticle on Properties of Nanocomposite Membrane Made of Bacterial Cellulose

ABSTRACT The purpose of this study was to see the effect of adding TiO2 nanoparticles had on the characteristics of bacterial nanocellulose (BNC)-based membranes. Pellicles were created from the pineapple peel waste extract, and to obtain BNC, pellicle was disintegrated in six cycles using high-pressure homogenizer at 150 bar. The concentrations of TiO2 nanoparticles in the membrane reinforcement solution were 0.5, 1.0, 1.5, 2.0, and 2.5 wt.%. They were sonicated and dried in an oven at 60°C for 8 h. X-ray diffraction, Fourier transform infrared spectroscopy, roughness test, mechanical properties, and scanning electron microscopy were investigated to explore its claims. The results revealed that diffraction pattern of BNC/TiO2 membrane has a new peak at 25.05° that ensures the presence of TiO2 nanoparticles as well as diffraction peak occurred at 22.49°, which indicates the presence of cellulose Iβ. Moreover, the addition of TiO2 nanoparticles until 1.5 wt.%, the crystallinity index is relatively same and the optimum strength of 99.5 MPa was attained. Further, improvement in addition of TiO2 nanoparticle at 2 wt.% showed a decline in crystallinity index as 80.16% to 74.72% at 2.5 wt.%. The morphology of the membrane surface revealed that TiO2 nanoparticles were still agglomerated and not equally distributed across the BNC membrane, leading to increase in surface roughness.

EFFECTS PARTICLES CONCENTRATION OF Al2O3 AND TiO2 TO CONVECTION COEFFICIENT ON DOUBLE PIPE HEAT EXCHANGER

Heat exchanger is a device used to transfer heat energy from a fluid to in another fluid. Each fluid has different characteristics. Value of convection heat transfer is determined by the value of the convection heat transfer coefficient (h) which depends on the dimensions and flow conditions. The fluid with the additional of Al2O3 nanoparticles (aluminum oxide) and TiO2 (Titanium dioxide) has great potential for cooling applications. The purpose of this study was to analyze the effect of Al2O3 and TiO2 particle concentration on the value of the convection heat transfer coefficient in the double pipe heat exchanger with circular straight pipes. Cooling fluid used is pure water, the fluid with the addition of Al2O3 nanoparticles and fluid with the addition of TiO2 nanoparticles at concentrations of respectively 40 ppm and 60 ppm. Flow used in a heat exchanger is the flow of counterflow type. Changes in temperature controlled 95 ° C for hot fluid, 17ºC for cooling fluid. The results show the influence of Al2O3 and TiO2 nanoparticles in the fluid characteristics and an increase in the value of the convection heat transfer coefficient is influenced by the amount of concentration on mixing nanoparticles in the cooling fluid.

High‐Performance Natural Graphite Anode for Lithium‐Ion Batteries: Using TiO2 as an Additive

AbstractIn this study, an attempt has been made to improve the performance of natural graphite anode using TiO2 nanoparticles additive. In this method, high‐performance electrodes have been achieved by addition of TiO2 nanoparticles to base graphite active material, which is able to offer supplementary effects. TiO2 emulsions with different concentrations of 10 %, 20 %, and 100 % are applied to prepare the binder solvent. The graphite anode made with 10 % concentration of TiO2 emulsion (NG−T10) shows the best performance in comparison with other samples. The Nano‐scale images of the scanning electron microscope (SEM) affirm the existence of a uniform coating on the surface of the natural graphite particles for the NG−T10 electrode. Energy‐dispersive X‐ray (EDX) spectroscopy on the NG−T10 sample clearly indicates the Ti element signal. According to atomic force microscopy (AFM) images, an increment in surface roughness can provide a more effective surface and improve wettability, resulting in better electrochemical performance of NG−T10. The charge‐discharge test of the NG−T10 half‐cell represents an excellent cycle performance without any capacity degradation during 100 cycles at 0.5 C. However, the value of capacity retention for bare natural graphite (BNG) is 90.7 % in the same conditions. The electrochemical impedance spectroscopy (EIS) results indicate that the existence of TiO2 nanoparticles in NG−T10 improves the resistance of solid electrolyte interface (SEI) film and charge‐transfer resistance. The NG−T10 also enhances the pouch cell capacity at various current densities up to 4 C.

Preparation and application of titanium dioxide nanoparticles in offset ink

TiO2 nano pigments in pure crystallographic forms (anatase) were prepared via a hydrothermal approach. The produced pigments were investigated physiochemically by several techniques, then they were utilized in paper-coating mixtures and their effect on the properties of coated papers was investigated. XRD revealed that these pigments produced a pure anatase phase pigment. TEM showed that the crystallite size for anatase is 50 nm. Whether optical or physical properties for the treatment before and after application were tracked. Although TiO2 is applied as a white dye, it provided good results on the black ink that is used in dyeing, whether ordinary TiO2 or that in the range of nano, in small quantities. The titanium oxide nanoparticles gave better results because of the increase in the surface area and optical or electromagnetic properties obtained when converting it to the range of nanoscale. Most interestingly, the addition of TiO2 nanoparticles provided an improved ink that can carry out heat, humidity, oxygen, sunlight, and vibration for a long time, as indicated by the accelerated aging test. Thus, the prepared nano pigments of the TiO2 phase could be applied in jobbing offset ink and commercial paper sheets as a promising and novel pathway.

Nano-enhanced sulfonated poly(arylene ether sulfone) composite membranes and their characterization

Chlorine is a widely used oxidizing agent in desalination to control bacteria that cause biofouling. The lack of chlorine resistance in commercial desalination membranes urged the development of an alternate polymer material. In this study, commercially available copolymer (SES0005, AquafoneTM), resistant to dissolved chlorine in water, has theoretical IEC of 2.08 meq.g-1 is blended with 0.5-15 %(w/w) TiO2 nanoparticles of <25 nm diameter and 45-55 m2.g-1 surface area by using ball milling device. SEM-EDS (Scanning Electron Microscope-Energy Dispersive Spectroscopy) result supports TiO2 content and uniform distribution. The chlorine stability of membranes was evaluated in sodium hypochlorite solution from 100 to 2000 ppm (pH 9). TGA and FT-IR analysis were performed for these membranes. The 1.5 %(w/w) TiO2 nano-enhanced membrane water retention is 23 % which is ∼53 % higher than that of pristine (15 %) membrane. Tensile strength of pristine and 0.5 %(w/w) TiO2 nano-enhanced membrane is 23, and 44 MPa, respectively. TiO2 nanoparticle addition improved dimensional and mechanical properties. This study attempts to correlate the SES polymer-TiO2 interactions with the characterization techniques.

Physical and Chemical Processes of Structure Formation of (BeO+TiO2)-Ceramics with the Addition of TiO2 Nanoparticles

This paper describes in detail the solid-phase sintering mechanism of BeO ++ ceramics in the 1520–1550 °C temperature range. It is shown that the structural elements are formed due to the processes of pore disappearance and grain growth in the process of ceramic shrinkage during sintering. It is found that under the influence of TiO2 nanoparticles it is possible to increase the sintering temperature of such ceramics by 30 °C, which promotes the transformation of the crystal structure of TiO2 into a more conductive Ti3O5 with an orthorhombic structure. The mechanism of the slowing down of the grain boundary movement by the second phase impurity as the segregation of nano impurities on the grain boundary is described. The calculation of binding energy of spontaneous chemical reactions during sintering of ceramics is performed, chemical elements and compounds related to conductive phase in ceramics of BeO ++ composition atsintering temperature 1550 °С are determined. It is shown that the specific conductivity of the synthesized nanocomposite material increases in comparison with the ceramics consisting of micropowders in the frequency range of 100 Hz–100 MHz, at a sintering temperature of 1550 °С.

Surface smoothening and formation of nano-channels improved mono-selectivity and antifouling property in TiO2 incorporated cation exchange membrane

Green liquor solution (GLS) is waste pollutant from pulp and paper mills. Causticization process is a common treatment method for GLS, which is energy intensive and environmentally unsafe, because of high operating cost, and solid waste generation. We reported synergetic effect of titanium dioxide nanoparticle (TiO2) incorporated sulfonated PEEK, on the performance cation exchange membrane (CEM), for producing NaOH from industrial GLS by electro-electroldiaysis (EED). Reported composite CEM was studied for morphology, physicochemical, electrochemical properties. The counter-ion transport number, stability and antifouling properties of CEM were significantly improved after the addition of TiO2 nanoparticles in the sulfonated PEEK membrane matrix. Two compartment EED cell (active membrane area: 66 cm2) was used to perform the experiments for producing NaOH using industrial GLS at 60 mA·cm−2 constant current density. The reported results shed light on production of NaOH along with prevention of sulfur scaling in treatment of wood based pulp and paper mills GLS stream. The modified membrane named SPK-T-5 (5 wt% of TiO2) by utilizing containing sulfonated polymer matrix outperforms an increasing trend of NaOH production along with notable sulfur antifouling. The obtained research outcomes are expected to be a valuable source for NaOH production with the aim of zero solid discharge practice for pulp and paper mills.

Visible Light-Induced Photocatalyst with Au/TiO2 Nanocomposites Fabricated through Pulsed Laser-Induced Photolysis

Gold–titanium oxide nanocomposites (Au–TiO2 NCPs) were fabricated through pulsed laser-induced photolysis (PIPS) and verified to be usable for the visible light catalytic degradation of methylene blue (MB). The PIPS method can produce a sufficient amount of NCPs quickly and has potential to be commercialized. In contrast to other studies, we clarified the optical spectrum of the light sources, including peak power, bandwidth, and total intensity used for photodegradation reactions and discovered that the photodegradation efficiency of the produced Au–TiO2 NCPs in the wavelength range of 405 nm could reach 37% in 30 min due to the charge transfer between Au and TiO2. The control experiment shows that the addition of individual Au and TiO2 nanoparticles (NPs) to an MB solution has no enhancement of degradation ability under visible light illumination. The photodegradation of Au–TiO2 NCPs can be further improved by increasing the concentrations of auric acid and TiO2 NPs in a precursor under PIPS fabrication.

Study of mechanical properties and wear resistance of nanostructured Al 1100/TiO2 nanocomposite processed by accumulative roll bonding

Aluminum (Al) composites have been extensively developed for automotive applications due to their high specific strength. Therefore, in this study, an Al-titanium dioxide (TiO2) nanocomposite was processed using the accumulative roll bonding (ARB) process. The mechanical characteristics of monolithic and nanocomposites specimens made with 0, 1, 2, and 3 wt% TiO2 nanoparticles as reinforcement were studied at several ARB passes. According to the microstructure of the composites, rolling after five passes achieves a homogenous distribution of reinforcement particles, ultrafine and elongated grains of the matrix. After five ARB passes, the TiO2 particles were uniformly dispersed. Finally, scanning electron microscopy and energy dispersive spectroscopy revealed that the Al-TiO2 nanocomposite had an appropriate dispersion of TiO2 nanoparticles. Vickers microhardness improves as the number of accumulative roll bonding passes increases. Furthermore, after five passes, Vickers microhardness testing revealed that the sample with 3%TiO2 has the greatest hardness value of 112 HV, which is significantly greater than the 44 HV hardness value of the ARB-processed aluminum. The mechanical properties of the specimens, yield and ultimate strengths, improved with the addition of TiO2 nanoparticles. Due to good bonding among the components, mechanical parameters such as microhardness and tensile strength were more than three times better than the Al matrix.

The effect of TiO2 nanoparticles size on Cd (II) removal by the paddy crusts from waterbody

The influence of nanoparticles (NP) on the accumulation of heavy metals in the paddy crust (PC) was unclear. This experiment explored the potential effects and mechanism of TiO2 NP with different particle sizes on Cd removal by PC from waterbody. All the TiO2 with size of 25 nm (T25), 100 nm (T100) and 2000 nm (T2000) can promote the Cd uptake by the PC, and with the sequence: T100 > T25 > T1000. Especially, 0.1 mg/L T100 can enhanced ~45% Cd removal comparing with pristine PC, and the Cd uptake capacity reached as high as 92 mg/g. After treatment of 72 h, the PC+T100 can reduce Cd in the acidic coal drainage from 0.48 mg/L to 0.009 mg/L, with removal efficiency of 98%. The total concentration of surface adsorptive site number of PC+T100, PC+T25 and PC was 0.87 ± 0.03, 0.78 ± 0.07 and 0.67 ± 0.04, respectively. The TiO2 stimulation to PCs secreted the extracellular substance and then increased the content of amino/hydroxyl adsorptive sites by 30–70%. T100 can stimulate high EPS-producing algae and bacteria, whereas most T25 can only penetrate the cell walls of low EPS-producing microorganisms. T100 can stimulate not only the thick sheath layer of Oedogonium, the main component of PC, but also the thin layer of algae and bacterium. And induce it to produce a large amount of protein, phospholipids, etc. T25 can only stimulate the Microcystics, Chlorococcum, Scenedesmius and bacteria with thin cell membranes to produce low extracellular substance. However, T25 would easily enter the cell trough thin cell membranes, result in that the Cd attached to T25 to penetrate the intracell. Therefore, the non-EDTA-exchangeable Cd fraction in PC+T25 was 55.48%, higher than 36.82% of PC+T100, and 21.52% of PC. Our investigation demonstrated that the addition of TiO2 NP with appropriated size in PC was a potential efficient method to remove the heavy metal from waterbody.

Effect of Solvent on Optical Properties and Surface Topography of Nanocomposite Conjugated Polymer Thin Film

The addition of TiO2 nanoparticles (NPs) to a white-emission conjugated polymer (CP) blend of poly(9,9-dioctylfluorene-2,7-diyl) (PFO) and poly(2-methoxy-5(2-ethylhexyl)−1,4-phenylenevinylene (MEH-PPV) enhanced the optical properties. However, the agglomeration of the nanoparticles restricted enhancement. This drawback was successfully overcome in this study. The highly polar solvent chloroform was mixed with toluene and used to prepare thin films of the blends. Solution blending and spin-coating techniques were used to prepare thin films with different TiO2 nanoparticle contents. In addition, pure toluene and chloroform were investigated as solvents for the nanocomposite blend. These three cases were compared by studying the emission spectra, absorption spectra, Commission Internationale d’Eclairage coordinates (CIE), field emission scanning electron microscopy (FE-SEM) images and scanning probe microscope (SPM) images. The average roughness, quenching constant, and energy transfer probability were calculated. The optimum physical properties of the thin film were achieved using nanoparticles at 15wt% and applied to the binary blend with a mixture of equal amounts of toluene and chloroform. Although chloroform is better for nanoparticle distribution, toluene is mandatory for obtaining the highest yield of PFO.

Characterization and performance evaluation of Cu-based/TiO2 nano composites

Copper and copper alloys are used in industrial applications and food contact surfaces due to their desirable properties; copper metal matrix composites have been exciting researchers' attention in recent years since they can offer many valuable characteristics. The present study investigated the effects of the TiO2 nanoparticles addition with different weight percent on the hardness and corrosion behavior of copper nanocomposites. The powder metallurgy method was used to fabricate the Cu/TiO2 reinforced with different weight fractions of TiO2 nano particles up to 12 wt.%. The corrosion behavior of fabricated specimens is evaluated using potentiodynamic polarization curves and electrochemical impedance spectroscopy in different solutions. These solutions were 3.5wt.% NaCl, 0.5 NaOH and 0.5 M H2SO4 reflected different pH. The results showed that the addition of TiO2 nano particles improves pure copper's hardness. The hardness of pure copper increased from 53 to 91 HV by adding 12 wt.% TiO2. The corrosion current density (Icorr) of copper nanocomposites test specimens was higher than Icorr of pure copper in all test solutions. As TiO2 nano particles increase, the corrosion resistance of Cu nano composites decreased. All test specimens exhibited little corrosion current density in 3.5 wt.% NaCl solution as compared with other test solutions.

Physical properties and DFT calculations of the hybrid organic polymeric nanocomposite thin film [P(An+o-Aph)+Glycine/TiO2/]HNC with 7.42% power conversion efficiency

Copolymer of aniline and ortho aminophenol was prepared by using the oxidative polymerization method with ferric chloride as an oxidizing agent in the occurrence of polyethylene glycol (Mol. Wt. 200) as a soft template. The microporous structure thin films were fabricated from the hybrid material of titanium oxide/copolymer (2-aminophenol and aniline) + glycine [P(An+o-Aph)+Gl/TiO2]HNC via a physical vapor deposition (PVD) method. The effect of the addition of glycine and TiO2 nanoparticles (NPs) on the physical properties of copolymer [P(An+o-Aph)] was discussed in light of the study of the crystallinity and optical properties. The addition of glycine increases the crystallinity of the resulting blend with the copolymer. The average crystallite size of TiO2 is ≈ 25 nm. The interaction between the blend and TiO2 was physical. The copolymer showed an absorbance of 1.18 at the wavelength (λ) 374 nm, which increased to 1.26 at λ= 440 nm after glycine addition, also increased to 1.53 at λ= 486 nm after TiO2 loading. Due to glycine blending and TiO2 addition, significant changes in the absorption index and indirect/direct bandgap of the copolymer have been detected. The materials Studio 7.0 program on TDDFT/DMol3 was used to optimize the molecular structure and perform the frequency calculations for the crystal models and isolated molecules. The DFT-Gaussian09W-vibration values are quite similar to the experimental data either in the structure or in the optical properties. The power conversion efficiency (η) of the blend Au/[P(An+o-Aph)+Gl]B/p-Si/Al heterojunction is 5.30 %, which increased to η=7.42% by loading the [TiO2]NPs to blend. The improvements in optical illuminations properties suggest the use the hybrid nanocomposite films in the polymers solar cell application.

Novel 8%‐TiO2‐nanoparticle‐reinforced dense polycrystalline bovine hydroxyapatite bioceramic

AbstractThis study aimed to produce and characterize the microstructure and mechanical properties of dense polycrystalline bovine hydroxyapatite (DPBHA) bioceramics with 5% and 8% of TiO2 nanoparticles after final synthetization for future use in dental implants. Structural characterization was obtained from analyzes by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscope, energy dispersive spectroscopy, and relative density and apparent porosity. The mechanical characterization was performed by measuring the fracture toughness after three‐point flexural strength (FS) test. The microstructural characterization results showed no secondary phase formation and nonhomogeneous nanoparticle dispersion in HA matrix. DPBHA/Np8% (2.9 ± 0.09 g/cm3) exhibited significantly greater density than DPBHA (2.7 ± 0.03 g/cm3) (p = 0.011) and DPBHA/Np5% (2.7 ± 0.05 g/cm3) (p = 0.041). DPBHA (0.9%) had the smallest porosity followed by DPBHA/Np8% (3.4%). DPBHA/Np5% (4.5%) exhibited the greatest proportion of pores. Pure HA (51.7 ± 10.3 MPa) and DPBHA/Np8% (47.4 ± 6.4 MPa) had significant greater FS (p < 0.001) than DPBHA/Np5% (28.8 ± 3.1 MPa). DPBHA (0.43 ± 0.01 MPa m1/2) and DPBHA/Np8% (0.40 ± 0.06 MPa m1/2) presented greater KIc than DPBHA/Np5% (0.23 ± 0.02 MPa m1/2) (p < 0.003; p < 0.007). In conclusion, 8% TiO2 nanoparticle addition to this synthesis would be a promising HA blend, as mechanical properties were similar, and the relative density/apparent porosity showed superior results than those of the DPBHA.