The microstructure, optical and gas sensing properties of bilayer TiO<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="d1e1291" altimg="si61.svg"><mml:msub><mml:mrow/><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>/ZnO systems in terms of annealing temperature

Kheiri, Fariba; Soleimanian, Vishtasb; Varnamkhasti, Mohsen Ghasemi; Mokhtari, Azam

doi:10.1016/j.mssp.2020.105462

Cited by 13 publications

(5 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Field Emission Scanning Electron Microscope (FESEM) images show that the ZnO concentration has a considerable impact on the final nanocomposite's shape. These findings are in agreement with those of other researchers [16]. To determine the correct quantity of materials contained in samples, chemical composition analysis is very necessary.…”

Section: Resultssupporting

confidence: 92%

Enhancing Gas Sensing Performance of TiO2-ZnO nanostructures: Effect of ZnO Concentration

Oleiwi,

Abdul Kareem

2023

IHJPAS

View full text Add to dashboard Cite

Gas sensors based on titanium dioxide (TiO2) and zinc oxide (ZnO) nanocomposites are considered energy-saving devices that are utilized to find dangerous or harmful gases in an environment. The performance of nitrogen dioxide (NO2) gas sensors have been improved by spin-coating a TiO2 and TiO2:ZnO nanocomposite with varying concentrations (90TiO2:10ZnO, 70TiO2:30ZnO, and 50TiO2:50ZnO). To correlate structural properties with gas-sensing behavior, structural and morphological characterization has been done using FESEM, XRD, and EDX. Without any ZnO-specific crystalline phase, TiO2 X-ray diffraction was found to be indexed in the anatase crystalline structure. The ZnO is synthesized in the wurtzite phase with (002) orientation and has a smooth surface, according to the morphologies and crystalline structure of the films, which also indicated the presence of ZnO components with various crystallite sizes and lattice strains. Responses to NO2 are increased by low ZnO content. Additionally, at the average operating temperature of 250 oC, TiO2:ZnO shows a good response.

show abstract

Section: Resultssupporting

confidence: 92%

Enhancing Gas Sensing Performance of TiO2-ZnO nanostructures: Effect of ZnO Concentration

Oleiwi,

Abdul Kareem

2023

IHJPAS

View full text Add to dashboard Cite

show abstract

“…The nanocrystallite sizes were increased from 11.3 nm (at 500 • C) to 33.4 nm (at 650 • C), supported by the size estimated via EFTEM and XRD analysis. The observed significant influence of the varying annealing temperatures on the TiO 2 NPs morphology was consistent with the other findings [29][30][31][32]. Earlier reports argued that the nanocrystallites at the film boundary are weakly attached to their neighbors.…”

Section: Resultssupporting

confidence: 91%

Photovoltaic Performance of Spherical TiO2 Nanoparticles Derived from Titanium Hydroxide Ti(OH)4: Role of Annealing Varying Temperature

et al. 2022

View full text Add to dashboard Cite

High-quality titanium dioxide (TiO2 or titania) nanoparticles (TiO2NPs) with tailored morphologies are desirable for efficient photovoltaic applications. In this view, some thin films containing spherical TiO2NPs were prepared on indium tin oxide (ITO) and silicon (Si) substrates from titanium hydroxide Ti(OH)4 using the unified sol-gel, spray and spin coating method followed by thermal annealing at different temperatures (in the range of 200–650 °C). Samples were characterized using various analytical tools to determine the influence of annealing temperatures on their structures, morphologies, and optical and photovoltaic characteristics. A field-emission scanning electron microscope (FESEM) and energy-filtered transmission electron microscopy (EFTEM) images of the annealed films displayed the existence of spherical TiO2NPs of average size in the range of 3.2 to 33.94 nm. XRD analysis of the films showed their amorphous nature with anatase and rutile phase. Optical UV-Vis spectral analysis of the annealed films exhibited a decrease in the bandgap energy from 3.84 to 3.24 eV with the corresponding increase of annealing temperature from 200 to 650 °C. The optimum films obtained at 500 and 600 °C were utilized as electron transport layers to fabricate the metal-insulator-semiconductor solar cells. The cells’ power conversion efficiency assembled with the spherical TiO2NPs-enclosed thin films annealed at 500 and 600 °C were 1.02 and 0.28%, respectively. Furthermore, it was shown that the overall properties and photovoltaic performance of the TiO2NPs-based thin films could be improved via thermal annealing.

show abstract

“…However, it slightly decreases when the annealing temperature reaches 800 °C, due to Zn-O bond breaking generated oxygen vacancy defects as indicated by the XPS results, which show a slightly increase in the area ratio of O D /(O D + O L ), results in the decrease of film density hence lower refractive index. 36 The highest refractive index of 1.98 at 630 nm was achieved for the ZnO film annealed at 700 °C. This value is very close to that for single crystalline ZnO (1.99), indicating a high density of the film.…”

Section: Resultsmentioning

confidence: 96%

Variation of Oxygen Vacancy Defects in sALD-ZnO Films Annealed in an Oxygen-Rich Ambient

Zhao

Sun

et al. 2021

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Oxygen vacancy defects play an important role in determining the properties of zinc oxide (ZnO) film. In this study, ZnO film prepared by a high-deposition-rate spatial ALD process was annealed in an oxygen-rich ambient. The variation of oxygen vacancy defects was analyzed. The results show that oxygen vacancy defects were suppressed by the annealing treatment, particularly at 500 °C–700 °C. As a result, the carrier concentration decreases with increasing annealing temperature, leading to the higher film resistivity. In addition, the oxygen atoms segregated to the ZnO/Si interface to form an interfacial oxide layer, leading to an oxygen-deficient ZnO film when annealed at 300 °C–400 °C and the decrease of oxygen atomic ratio when annealed at 500 °C–800 °C. The annealing treatment also induces higher crystallinity with larger crystallite size, leading to a higher mobility. The refractive index increases with annealing temperature at 300 °C–700 °C, possibly due to the structural relaxation, densification and crystallization of the film. However, the annealing treatment has little effect on the film transmittance due to the low optical loss.

show abstract

The microstructure, optical and gas sensing properties of bilayer TiO2/ZnO systems in terms of annealing temperature

Cited by 13 publications

References 49 publications

Enhancing Gas Sensing Performance of TiO2-ZnO nanostructures: Effect of ZnO Concentration

Enhancing Gas Sensing Performance of TiO2-ZnO nanostructures: Effect of ZnO Concentration

Photovoltaic Performance of Spherical TiO2 Nanoparticles Derived from Titanium Hydroxide Ti(OH)4: Role of Annealing Varying Temperature

Variation of Oxygen Vacancy Defects in sALD-ZnO Films Annealed in an Oxygen-Rich Ambient

Contact Info

Product

Resources

About