| 1. |
- Aaditya, V. B., et al.
(author)
-
Study of dielectric properties of polypyrrole/titanium dioxide and polypyrrole/titanium dioxide-MWCNT nano composites
- 2018
-
In: Journal of materials science. Materials in electronics. - : Springer. - 0957-4522 .- 1573-482X. ; 29:4, s. 2848-2859
-
Journal article (peer-reviewed)abstract
- The polypyrrole/titanium dioxide nano composites and polypyrrole/titanium dioxide-MWCNT nano composites were synthesized by chemical polymerization technique in the presence of an ammonium persulphate (oxidizing agent). Different concentrations viz. 15, 30, 45 and 60 wt% of titanium dioxide (TiO2) as well as mixture of TiO2-MWCNT in polypyrrole (PPy) respectively were used in the present study. The nano composites have almost spherical type shaped particles which have cluster formation as confirmed from SEM photos. The XRD graphs reveal that the PPy/TiO2 (PT) nano composites have shown the semi-crystalline nature and also, the graphs indicate the changeover of the structure of PPy/TiO2-MWCNT (PTM) nano composites from amorphous to semi-crystalline nature. From the FTIR figures, shift in wavenumber towards lower side is noticed in the case of PT and PTM nano composites when compared to PPy. The dielectric properties such as dielectric constant, dielectric loss and tangent loss have shown good behavior. This reveals that, the TiO2 as well as mixture of TiO2-MWCNT particles have shown strong dependence on PPy and helps to form good composites. So, the nano composites are good dielectric materials.
|
|
| 2. |
- Abdel-Baset, T. A., et al.
(author)
-
Effect of metal dopant on structural and magnetic properties of ZnO nanoparticles
- 2021
-
In: Journal of materials science. Materials in electronics. - : Springer. - 0957-4522 .- 1573-482X. ; 32:12, s. 16153-16165
-
Journal article (peer-reviewed)abstract
- Zn1-xRxO (R = Li, Mg, Cr, Mn, Fe and Cd) were obtained by using co-precipitation synthesis technique with constant weight percent of 3% from R ions. The phase composition, crystal structure, morphology, density functional theory (DFT), and magnetic properties were examined to comprehend the influence of Zn2+ partial substitution with R ions. X-ray diffraction shows that the ZnO lattice parameters were slightly affected by R doping and the doped sample crystallinity is enhanced. Our results show that introducing Cr, Mn and Fe along with Mg into ZnO induces a clear magnetic moment without any apparent distortion in the structural morphology. The spatial configuration of dopant atoms is determined from first-principles calculations, giving a better understanding of the position of the dopant atom responsible for the magnetism. The magnetic moments obtained from our calculations are 3.67, 5.0, and 4.33 mu B per dopant atom for Cr, Mn, and Fe, respectively, which agree with the experimental values. While Cr and Fe tend to form clusters, Mn has more propensity to remain evenly distributed within the system, avoiding cluster-derived magnetism.
|
|
| 3. |
- Abdullah, Omed Gh., et al.
(author)
-
Optical and structural investigation of synthesized PVA/PbS nanocomposites
- 2015
-
In: Journal of materials science. Materials in electronics. - : Springer Science and Business Media LLC. - 0957-4522 .- 1573-482X. ; 26:9, s. 6939-6944
-
Journal article (peer-reviewed)abstract
- Polymer nanocomposite based on polyvinyl alcohol (PVA) and lead sulfide (PbS) in the average radius of (1.88-2.23) nm, have been synthesized using the chemical reduction rote and solution casting technique for different concentrations of PbS. The characterization of the polymer nanocomposite films were carried out using UV-visible spectroscopy, SEM, and XRD. The effect of various concentration of PbS NP on the optical properties of the composite has been studied to understand the optimum conditions for the synthesis process. The nanocomposite film shows high UV and visible light absorptions in the wavelength range of (200-500) nm, which correspond to the characteristics of the PbS NPs. The significant decreasing trend of the direct allowed band gap of the nanocomposite was observed upon increasing the Pb source concentration, from (6.27 eV) for pure PVA to (2.34 eV) for 0.04 M PbS concentration, which is much higher than the energy gap of bulk PbS value (0.41 eV). The calculated values of the static refractive index of Cauchy dispersion model were in the range of (1.09-1.20). X-ray diffraction analysis confirmed the cubic nanocrystalline PbS phase formation.
|
|
| 4. |
- Aboulsaad, Mustafa, et al.
(author)
-
Thermal oxidation of sputtered nickel nano-film as hole transport layer for high performance perovskite solar cells
- 2019
-
In: Journal of materials science. Materials in electronics. - : Springer Nature. - 0957-4522 .- 1573-482X. ; 30:22, s. 19792-19803
-
Journal article (peer-reviewed)abstract
- The effect of rapid oxidation temperature on the sputtered nickel (Ni) films to act as a hole transport layer (HTL) for perovskite solar cell (PSCs) was investigated. A nano-sputtered Ni film with a thickness about 100 nm was oxidized at a range of different oxidation temperatures between 350 and 650 °C to work as HTL in an inverted p–i–n configuration. DC Hall measurement in van der Pauw configuration and photoluminescence spectroscopy were used to measure the charge’s mobility and extraction of nickel oxide (NiO) films. The behaviour of the carrier concentration measurements of NiO layers at different oxidation temperatures showed that the Ni layer oxidized at 450 °C had the highest carrier concentration among the other samples. The performance measurements of the fabricated PSCs showed that the nickel oxide hole-transporting layer which has been oxidized at the optimum oxidation temperature of 450 °C has the highest power conversion efficiency (PCE) of 12.05%. Moreover, the characteristic parameters of the optimum cell such as the open-circuit voltage (VOC), short-circuit current density (JSC) and fill factor (FF) were 0.92 V, 19.80 mA/cm2 and 0.331, respectively.
|
|
| 5. |
- Akbar, F., et al.
(author)
-
Graphene synthesis, characterization and its applications in nanophotonics, nanoelectronics, and nanosensing
- 2015
-
In: Journal of materials science. Materials in electronics. - : Springer Science and Business Media LLC. - 0957-4522 .- 1573-482X. ; 26:7, s. 4347-4379
-
Journal article (peer-reviewed)abstract
- In the last decade, as semiconductor industry was approaching the end of the exponential Moore's roadmap for device downscaling, the necessity of finding new candidate materials has forced many research groups to explore many different types of non-conventional materials. Among them, graphene, CNTs and organic conductors are the most successful alternatives. Finding a material with metallic properties combined with field effect characteristics on nanoscale level has been always a dream to continue the ever-shrinking road of the nanoelectronics. Due to its fantastic features such as high mobility, optical transparency, room temperature quantum Hall effect, mechanical stiffness, etc. the atomically thin carbon layer, graphene, has attracted the industry's attention not only in the micro-, nano-, and opto-electronics but also in biotechnology. This paper reviews the basics and previous works on graphene technology and its developments. Compatibility of this material with Si processing technology is its crucial characteristic for mass production. This study also reviews the physical and electrical properties of graphene as a building block for other carbon allotropes. Different growth methods and a wide range of graphene's applications will be discussed and compared. A brief comparison on the performance result of different types of devices has also been presented. Until now, the main focus of research has been on the background physics and its application in electronic devices. But, according to the recent works on its applications in photonics and optoelectronics, where it benefits from the combination of its unique optical and electronic properties, even without a bandgap, this material enables ultrawide-band tunability. Here in this article we review different applications and graphene's advantages and drawbacks will be mentioned to conclude at the end.
|
|
| 6. |
- Alshgari, Razan A., et al.
(author)
-
Manipulation of CuO morphology for efficient potentiometric detection of urea via slow nucleation/growth kinetics exerted by mixed solvents
- 2022
-
In: Journal of materials science. Materials in electronics. - : SPRINGER. - 0957-4522 .- 1573-482X. ; 33, s. 25250-25262
-
Journal article (peer-reviewed)abstract
- Controlling the reaction kinetics during the nucleation/growth of cupric oxide (CuO) nanostructures is very critical in order to achieve a specific and well-defined morphology. For this purpose, we have slowed down the reaction speed using a mixed solvent concept and successfully obtained a chain-like morphology of CuO nanostructures using hydrothermal method. The CuO chain-like morphology was synthesized using a 1:1 (v/v) ratio of ethylene glycol and water. The morphology and crystalline features of CuO were studied by scanning electron microscopy (SEM) and powder X-ray diffraction techniques. The high resolution transmission electron microscopy revealed 5 nm crystallite size for the CuO material prepared in the mixed solvents. The obtained results have shown that the prepared CuO chains had a monocline phase, containing only Cu and O as main elements as confirmed by energy dispersive spectroscopy. This unique morphology obtained from mixed solvent process has provided a better surface for the loading of urease enzyme, thus it enabled the development of sensitive and selective urea biosensor in phosphate buffer solution of pH 7.4. The physical adsorption method was used to immobilize urease enzyme onto the nano surface of CuO. The fabricated biosensor based on urease/CuO chains has shown a dynamic linear range from 0.0005 to15 mM with a low limit of detection 0.0001 mM. Additionally, a fast response time aroudn1s, h high selectivity, stability, repeatability, storage time, and reproducibility were observed. The effect of pH and temperature on the potentiometric signal of the developed biosensor was also examined. Importantly, the practical aspects of the fabricated urea biosensor were probed and the obtained percent recovery results revealed an outstanding performance. The strategy of using mixed solvent with equal volume ratio would be useful for the preparation of other metal oxides with improved catalytic properties for a wide range of clinical, biomedical and other related applications.
|
|
| 7. |
- Anghel, Clara, et al.
(author)
-
A gas phase analysis technique applied to in-situ studies of gas-solid interactions
- 2007
-
In: Journal of materials science. Materials in electronics. - : Springer Science and Business Media LLC. - 0957-4522 .- 1573-482X. ; 47:10, s. 3440-3453
-
Journal article (peer-reviewed)abstract
- An ultrahigh vacuum technique using mass spectrometry for in-situ investigations of gas-solid interactions is described in this paper. Examples of chemical reactions (oxidation, hydration) between solids and gas mixtures, dissociation of gases on solid surfaces, outgassing of solid materials and permeation of gases through membranes are discussed where the experimental arrangement is explained in detail. This Gas Phase Analysis (GPA) technique can be used at temperatures from room temperature to 1200 degrees C and at pressures up to 1 atm. Aspects related to sample preparation, isotopic gas mixture selection, data acquisition, calibration and interpretation of the experimental data are also addressed.
|
|
| 8. |
- Bandara, Tmwj, et al.
(author)
-
Efficiency enhancement and chrono-photoelectron generation in dye-sensitized solar cells based on spin-coated TiO2 nanoparticle multilayer photoanodes and a ternary iodide gel polymer electrolyte
- 2023
-
In: Journal of Materials Science-Materials in Electronics. - 0957-4522. ; 34:28
-
Journal article (peer-reviewed)abstract
- The effect of the thickness of a multilayer TiO2 photoanode on the performance of a dye-sensitized solar cell (DSC) made with a polyethylene oxide-based gel polymer electrolyte containing ternary iodides and performance enhancer 4-tert-butylpyridine is studied. Multilayer photoanodes consisting of up to seven layers of TiO2 nano-particles (13 nm and 21 nm) are prepared by spin coating of successive layers. XRD results confirm the predominant presence of the anatase phase of TiO2 in the multilayer structure after sintering. The SEM images reveal the formation of a single TiO2 film upon sintering due to merging of individually deposited layers. The photocurrent density (J(SC)) and the efficiency increase with the number of TiO2 layers exhibiting the maximum efficiency and J(SC) of 5.5% and 12.5 mA cm(-2), respectively, for the 5-layered electrode of total thickness 4.0 mu m with a 9.66 x 10(-8) mol cm(-2) surface dye concentration. The present study introduces a method of determining the rate of effective photoelectron generation and the average time gap between two successive photon absorptions where the respective results are 1.34 molecule(-1) s(-1) and 0.74 s for the most efficient cell studied in this work.
|
|
| 9. |
- Bandara, T M W J, 1968, et al.
(author)
-
Novel photo-voltaic device based on Bi_{1−x}La_xFeO_3 perovskite films with higher efficiency
- 2019
-
In: Journal of Materials Science: Materials in Electronics. - : Springer Science and Business Media LLC. - 1573-482X .- 0957-4522. ; 30:2, s. 1654-1662
-
Journal article (peer-reviewed)abstract
- Photovoltaic cells using polycrystalline La substituted bismuth iron oxide, Bi1−xLaxFeO3, (0.1 ≤ x ≤ 0.4), films as the light harvesting component were investigated in this work. A novel cell set-up utilizing a double layered TiO2 film as top contact and a thin layer of quasi-solid polymer electrolyte as back contact was used and a significant enhancement in cell efficiency was observed for assemblies based on x ≥ 0.2 samples, coincident with a structural transition of Bi1−xLaxFeO3 from ferroelectric to non-ferroelectric. The power conversion efficiency of the PV device was 0.13% for the cell with x = 0.2 at 1 sun irradiation. The short circuit current density for this La composition was 0.35 mA cm−2. A hysteretic behaviour was observed for higher La compositions when the scanning is from open-circuit (OP) to short-circuit (SC) which may be attributed to polarization effects. The results at x ≥ 0.2 show an improved performance with respect to BiFeO3 based systems, suggesting the stabilization of the non-ferroelectric crystal structure leads either to a more efficient separation of photo-generated electron–hole pairs and/or enhanced charge transport. The findings represent a step towards the realisation of facile to fabricate, inorganic solid state photovoltaic devices.
|
|
| 10. |
- Bandara, Tmwj, et al.
(author)
-
Novel photo-voltaic device based on Bi1-xLaxFeO3 perovskite films with higher efficiency
- 2019
-
In: Journal of Materials Science-Materials in Electronics. - : Springer Science and Business Media LLC. - 0957-4522 .- 1573-482X. ; 30:2, s. 1654-1662
-
Journal article (peer-reviewed)abstract
- Photovoltaic cells using polycrystalline La substituted bismuth iron oxide, Bi1-xLaxFeO3, (0.1x0.4), films as the light harvesting component were investigated in this work. A novel cell set-up utilizing a double layered TiO2 film as top contact and a thin layer of quasi-solid polymer electrolyte as back contact was used and a significant enhancement in cell efficiency was observed for assemblies based on x0.2 samples, coincident with a structural transition of Bi1-xLaxFeO3 from ferroelectric to non-ferroelectric. The power conversion efficiency of the PV device was 0.13% for the cell with x=0.2at 1 sun irradiation. The short circuit current density for this La composition was 0.35mAcm(-2). A hysteretic behaviour was observed for higher La compositions when the scanning is from open-circuit (OP) to short-circuit (SC) which may be attributed to polarization effects. The results at x0.2 show an improved performance with respect to BiFeO3 based systems, suggesting the stabilization of the non-ferroelectric crystal structure leads either to a more efficient separation of photo-generated electron-hole pairs and/or enhanced charge transport. The findings represent a step towards the realisation of facile to fabricate, inorganic solid state photovoltaic devices.
|
|
