Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Titanium dioxide

Effect of Growth Time on the Structural, Optical and Electrical Properties of the 1%Fe doped TiO2 p-type Synthesized by Hydrothermal Technique

Sattar J. Hashim; Odai N. Salman; Khaleel I. Hassoon

Engineering and Technology Journal, 2021, Volume 39, Issue 7, Pages 1133-1143
DOI: 10.30684/etj.v39i7.1874

In this work, a hydrothermal technique is employed to prepare titanium dioxide films on fluorine-doped tin oxide (FTO) substrates. A low-cost homemade autoclave was used to fabricate iron-doped -TiO2 films (1at. %Fe) at different reaction times from 1 to 4 hours.  X-ray diffraction (XRD) patterns showed that the predominant phase is rutile (R-TiO2) with peaks at (101), (002), and (112). The XRD results showed that with increasing reaction time the peaks become sharper and narrowed. The images of the field emission scanning electron microscope (FESEM) showed that with increasing reaction time the films appeared to have vertically aligned TiO2 nanorods. The atomic force microscope (AFM) results illustrated that surface roughness and the root means square was decreased with increasing the reaction time. UV-visible spectroscopy analysis revealed that the energy bandgap value (Eg) decreased with reaction time up to 3 hours. Urbach energy for the grown films was found to be decreased with increasing growth time. The electrical measurements indicated that all TiO2 films had p-type conductivity.

Influence of Nanocermic on Some Properties of Polyetheretherketone Based Biocomposites

Alaa A. Mohammed; Jawad K. Oleiwi; Emad S. Al-Hassani

Engineering and Technology Journal, 2020, Volume 38, Issue 8, Pages 1126-1136
DOI: 10.30684/etj.v38i8A.703

Polyetheretherketone (PEEK) materials belong to a group of high-performance thermoplastic polymers thermoplastic that has been proposed as a substitute for metals in biomaterials. In this research, in order to improve the performances of PEEK, nano titanium dioxide (n-TiO2) and nano-hydroxyapatite (n-HAp) were incorporated into PEEK loading up to (1.5 wt%) to fabricate PEEK composites by using a method of melt-blending and hot compressing. Properties, such as compression, density, the morphology of fracture, and element analysis were examined for preparing samples. The results showed that the compression and density properties improved with increased weight fraction for two types of reinforcement, but the higher values obtained at (1.5 wt%) for two types of powders. It was found the higher compression strength and compression modulus obtained when reinforced with (1.5% n-HAp) which equal to (107.632 MPa and 3.991 GPa) respectively, than for samples reinforced with (1.5% n-TiO2) which equal to (91.579 MPa and 3.123GPa) respectively, while the density results have opposite behavior, it was found the higher values obtained when reinforced with (n-TiO2) than for samples reinforced with (n-HAp) and at (1.5% n-TiO2) the higher density, which equal to (1.3656) while at (1.5% n-HAp) which equal to (1.3425). Field emission scanning electron microscope (FESEM) manifested, that the fracture morphology transferred from brittle to ductile when reinforced with nano particles. Also, EDS analysis elucidated an identically uniform distribution of n-TiO2 and n-HAp

Optical Characterizations of RF-Magnetron Sputtered Nanocrystalline TiO2 Thin Film

Azhar K. Sadkhan

Engineering and Technology Journal, 2018, Volume 36, Issue 2B, Pages 156-159
DOI: 10.30684/etj.36.2B.11

TiO2 nanocrystalline thin films are widely used as antireflection coating
in solar cell, in this paper, RF magnetron sputtering technique is used to prepare
TiO2 thin film on glass substrates, TiO2 thin films deposited under different
powers (75,100,125 and 150) Watt for (1.5) hour resulted in different layer
thickness (62.5,88,118 and 132.6) nm respectively. The optical properties
examined by UV-VIS spectroscopy. TiO2 thin films exhibit a high transparency in
the region from about 350 nm above, we suggest that these results indicate the
most suitable growing conditions for obtaining high quality sputtered TiO2 thin
films with higher transparence performance for solar cell application. the optical
absorbance coefficient for all films were genuinely high esteems coming to above
104 cm-1, which implies that there is allowed direct transitions, the energy gab
reach to the typical value of the bulk TiO2 (3.5) eV.

The Growth Characteristics of RF-Magnetron Sputtered Nanocrystalline TiO2 Thin Films

Azhar K. Sadkhan; Suaad A. Mohammed; Mohammed K. Khalaf

Engineering and Technology Journal, 2018, Volume 36, Issue 2B, Pages 128-130
DOI: 10.30684/etj.36.2B.6

In this paper, RF Magnetron sputtered TiO2 thin films deposited on
glass slices at various powers (75,100,125 and 150) Watt for (1.5) hour and
different thickness (62.5-88-118 and 132.6) nm, the TiO2 thin films annealed with
400°C for 2 hour and the morphology and structure of these films are described
by X-ray diffraction XRD and atomic force microscopy AFM to show the phase
structure. X-ray diffraction investigation uncovered that the crystalline size of the
TiO2 thin films displays an expanding pattern with increasing the sputtering
power. The preferred orientation of (101) was watched for the films deposited
with sputtering power of (75,100,125 and 150) Watt.

The Use of Photocatalytic Cementitious Coatings to Reduce Nitric Oxide from Ambient Air

ayat Hussian; Riyad H. Al Anbari; Maan S. Hassan

Engineering and Technology Journal, 2018, Volume 36, Issue 1C, Pages 17-21
DOI: 10.30684/etj.36.1C.4

Titanuim dioxide represents a novel photocatalyst material that can be used in different ways for air pollutants remediation. Air pollutants that are spreaded in the surrounding air could be transferred to more complex materials, especially in the presence of sunlight. To study the possibility for the reduction of these pollutants a laboratory tests have been conducted on the coated specimen substrate by using nitric oxide as pollutant gas, and there efficiency in gas removal was monitored with time. Two different particle sizes of TiO2 have been used; micro with particle size range between 150-200 nm and nano PC105 with particle size 20+ 5 nm, both are 100% anatse. Two coatings methods were applied on cementitious substrate material dip and spray to study the photochemical reaction with TiO2, aqueous solution prepared by dispersing 3g/L of TiO2 with deionized water and ethanol. Results show that using nano and micro size TiO2 aqueous solutions were effective in the removal of nitric oxide
with variations in the time consumed for the removal. Using nano aqueous solution in both dip and spray methods gives the same removal efficiency reached to 98.85% ,while using micro aqueous solution the removal reached to 98.08% when dip method was used and 87.69% when spray method was used.

Annealing Effect on the Growth of Nanostructured TiO2 Thin Films by Pulsed Laser Deposition (PLD)

Sarmad S.Kaduory; Ali A.Yousif; Adawiya J. Haider; Khaled Z.Yahya

Engineering and Technology Journal, 2013, Volume 31, Issue 4, Pages 460-470
DOI: 10.30684/etj.31.4B.6

In this work, Nanostructured TiO2 thin films were grown by pulsed laser deposition (PLD) technique on glass substrates at 300 °C. TiO2 thin films were then annealed at 400-600 °C in air for a period of 2 hours. Effect of annealing on the structure, morphology and optical properties were studied. The X-ray diffraction (XRD) and Atomic Force Microscopy (AFM) measurements confirmed that the films grown by this technique have good crystalline tetragonal mixed anatase and rutile phase structure and homogeneous surface. The study also reveals that the RMS value of thin films roughness increased with increasing annealing temperature .The optical properties of the films were studied by UV-VIS spectrophotometer. The optical transmission results shows that the transmission over than ~65% which decrease with the increasing of annealing temperatures. The allowed indirect optical band gap of the films was estimated to be in the range from 3.49 to 3.1 eV. The allowed direct band gap was found to decrease from 3.74 to 3.55 eV with the increase of annealing temperature. The refractive index of the films was found from 2.27 -2.98 at 550nm. The extinction coefficient increase with annealing temperature.