Atomic Weight Percentage Research Articles

Annealing effects on 100 keV silicon negative ions implanted SiO2 thin films

SiO2 thin film of thickness 300 nm grown on p-type silicon substrate was implanted with 100 keV silicon negative ions for the fluences of 1 × 1016, 5 × 1016, and 1 × 1017 ions cm−2. The implanted samples were investigated using an energy-dispersive X-ray (EDX) spectroscopic technique, and the samples were annealed at a temperature of 900 oC under N2 ambient. Ultraviolet–visible near infrared (UV-Vis-NIR) spectroscopy has been used to investigate the implanted SiO2 thin film samples before and after thermal annealing. EDX results revealed an increase in the atomic percentage and weight percentage of silicon ions as compared to oxygen ions in SiO2 thin film. This may be due to the increase in the concentration of silicon ions with the increase of implanted ion fluences within the SiO2 thin film. UV-Vis-NIR studies showed higher transmittance for thermally annealed samples as compared to non-annealed samples. This may be attributed to the creation of a new SiOx phase in the SiO2 matrix at higher temperatures. UV-Vis-NIR studies also exhibited an increase in the energy band gap value after thermal annealing. This effect may be related to the formation of silicon nanoclusters in SiO2 thin film.

Electrochemical oxidation of Florfenicol in aqueous solution with mixed metal oxide electrode: Operational factors, reaction by-products and toxicity evaluation

Veterinary antibiotics have become an emerging pollutant in water and wastewater sources due to excess usage, toxicity and resistance to traditional water and wastewater treatment. The present study explored the degradation of a model antibiotic- Florfenicol (FF) using electrochemical oxidation (EO) with Ti–RuO2/IrO2 anode. The anode material was characterized using SEM-EDS studies expressing stable structure and optimal interaction of the neighboring metal oxides with each other. The EDS results showed the presence of Ru, Ir, Ti, O and C elements with 6.44%, 2.57%, 9.61%, 52.74% and 28.64% atomic weight percentages, respectively. Optimization studies revealed pH 5, 30 mA cm−2 current density and 0.05 M Na2SO4 for 5 mg L−1 FF achieved 90% TOC removal within 360 min treatment time. The degradation followed pseudo-first order kinetics. LC-Q-TOF-MS studies revealed six predominant byproducts illustrating hydroxylation, deflourination, and dechlorination to be the major degradation mechanisms during the electrochemical oxidation of FF. Ion chromatography studies revealed an increase in Cl−, F− and NO3− ions as treatment time progressed with Cl− decreasing after the initial phase of the treatment. Toxicity studies using Zebrafish (Danio rerio) embryo showed the treated sample to be toxic inducing developmental disorders such as pericardial edema, yolk sac edema, spinal curvature and tail malformation at 96 h post fertilization (hpf). Compared to control, delayed hatching and coagulation were observed in treated embryos. Overall, this study sets the stage for understanding the effect of mixed metal oxide (MMO) anodes on the degradation of veterinary antibiotic-polluted water and wastewater sources using electrochemical oxidation.

The effect of the number of sulfonic acids in polysiloxanes as fillers for polymer electrolyte membranes in energy storage applications

A series of sulfonic acid-functionalized polysiloxanes (MASFPs) that can be used to reduce the cost and improve the properties of proton exchange membranes (PEMs) by acting as fillers have been synthesized. In this paper, we describe the synthesis of MASFPs with varying numbers of sulfonic acid groups with the aid of mercaptoethanol. An array of analytical techniques were employed to characterize the synthesized MASFPs. The broad peak observed in the X-ray diffraction pattern of MASFPs between 2θ = 15–25° signifies their amorphous characteristics. Analyses by infrared spectroscopy also identify MASFPs that contain stretching vibrations for –SO3H, –CH2, and Si–O– group. The thermogravimetric analysis demonstrates the thermal stability of these MASFPs. The surface morphology analysis of the MASFPs using FESEM and HRTEM revealed the presence of spherical particles that exhibited significant aggregation and distortion. By employing X-ray photoelectron spectroscopy (XPS) to determine the atomic weight percentage of sulfur present in the MASFPs, the number of sulfonic acids contained within was verified. The sulfur content of MASFPs is determined by XPS to be as follows: MASFP-4 > MASFP-3 > MASFP-2 > MASFP-1. The presence of Q4, Q3, T3, and T2 signals, as determined by 29Si MAS NMR analysis, confirms the polysiloxane formation. Preliminary studies of the composite membrane prepared using the MASFPs with perfluorosulfonic acid (PFSA:MASFP in 75:25 ratio) exhibited superior ionic conductivity (0.102 S/cm) and ion-exchange capacity (1.16 meq/g) in comparison to the commercial Nafion membrane. Overall, using a mercaptoethanol-assisted process to synthesize sulfonic acid functionalized polysiloxanes is an excellent way to increase the incorporation of sulfonic acids and it can be applied to the synthesis of various other inorganic nanofillers.

Photocatalytic Degradation of Acid Blue 25 Dye in Wastewater by Zinc Oxide Nanoparticles

This study investigates the photocatalytic degradation of Acid Blue Dye using zinc oxide nanoparticles synthesized from Senna siamea flower extracts (ZnO-S.S.). The synthesized nanoparticles were investigated using Transmission Emission Spectroscopy (TEM) and Scanning Electron Microscope (SEM), which made it possible to reveal the spherical shape of ZnO-S.S. nanoparticles. Themogravimetric Analysis – Differential Thermal Analysis (TGA-DTA) revealed high thermal stability of ZnO-S.S. with an insignificant weight loss as temperature increases from 600 °C to 846.9 °C. While Energy Dispersive X-ray analysis (EDX) reveals the elemental composition and atomic weight percentage as C (4.8%), O (11%), S (6%) and Zn (78.2%). The synthesized nanoparticles ZnO-S.S. used to degrade Acid Blue dye contaminated waste water under visible light irradiation. Exhibits an optimum degradation efficiency of 99% achieved in 150 minutes using a catalyst dosage of 150 mg at an initial acid blue concentration of 10 mg/L. The degradation process best conformed to the pseudo first order kinetics pathway. In conclusion the study established that the synthesized catalyst exhibits good efficiency and utility in degrading dye contaminated wastewater. However, further studies are recommended on the influence of other indicators such as light intensity, temperature and pH on the degradation process.

Effect of Different Passivation Treatments on Alkali Zn-Ni Coatings: Corrosion Resistance and Adhesion Performance of Geomet 321 and ML Black Coatings

This study aims to improve the corrosion properties of (AISI 1040) materials used in the automotive industry. For this purpose, two different coating techniques were applied to the same surface. As part of the research, different passivation processes (transparent, blue, yellow, and black) were applied to alkaline Zn-Ni coatings. Geomet 321 and Geomet ML Black coatings were deposited on the passivation layer to form a double-layer coating. In order to investigate the adhesion and corrosion effects of these coatings, a dry adhesion test, a water test, a humidity test, and a salt spray test were carried out, and cross-cut adhesion tests were carried out after each corrosion test. After all these tests, rust formation was analysed by visual analysis, and atomic weight percentages and coating thicknesses were examined by X-ray. The transparent passivation after the Zn-Ni coating fully satisfied both adhesion and corrosion protection requirements for 321 and ML Black coatings. No red rust formation was observed on the coating samples after the test; only partial white rust formation was observed, and no peeling of the coating layer was detected in the adhesion tests. As a result, the optimum result of the passivation processes used for Geomet 321+ML Black coatings applied after the Zn-Ni + passivation process was obtained with transparent passivated Zn-Ni coatings. Even after 1200 hours, no red rust was observed in passivated Zn-Ni coating+ Geomet 321+ Geomet ML Black.

TeO2 doped ZnO nanostructure for the enhanced NO2 gas sensing on MEMS sensor device

Severe health issues occur when human beings are exposed to NO2 gas, which is formed from combustion processes and reactions facilitated by sunlight. In order for safety measurements, NO2 gas sensors are highly needed at low concentration gas detections. ZnO gas sensor with the doping of TeO2 is developed using co-sputtering technique. ZnO/TeO2 heterojunction nanostructure is analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and energy dispersive spectroscopy (EDS) for structural study. Gas sensing properties were tested with Micro electro mechanical system (MEMS) devices, on which ZnO/TeO2 nanostructure is developed. This study focused on doping of 4 different variations of TeO2 with ZnO such as 0%, 2%, 4% and 8% atomic weight percentage (at.w%) of TeO2. Upon testing, 4% ZnO/TeO2 transpired to be best possible parameter for NO2 gas sensing. With maximum NO2 gas concentration of 1 ppm, 4% ZnO/TeO2 sensor exhibited 80% sensing response and with 200 ppb of minimum gas concentration, sensor had 42% response at optimal temperature of 100 oC. TeO2 doped ZnO sensor exhibits superior performance over pure ZnO sensor and has good selectivity over NO2 gas.

Synthesis and X-ray Diffraction Study of Se79 Te20 Pb1 Chalcogen Glass

Chalcogenide glasses have received much attention from researchers during the last few years because of their interesting optical, electrical, dielectric, thermal, and physical properties by changing the composition such as wide transmission range, high refractive index, good chemical durability, optical switching, and from amorphous to crystalline phase transition. In this paper, are taken in appropriate atomic weight percentages. Ternary Se₇₉Te₂ Pb₁ chalcogenide glass is prepared by conventional melt quenching technique. XRD method is used for the identification of crystalline materials. Thus, the absence of any sharp and prominent peak in the XRD pattern confirmed the amorphous nature of chalcogenide glass.

Characterising Hydroxyapatite Deposited from Solution onto Novel Substrates: Growth Mechanism and Physical Properties.

Whilst titanium, stainless steel, and cobalt-chrome alloys are the most common materials for use in orthopaedic implant devices, there are significant advantages in moving to alternative non-metallic substrates. Substrates such as polymers may have advantageous mechanical biological properties whilst other substrates may bring unique capability. A key challenge in the use of non-metal products is producing substrates which can be modified to allow the formation of well-adhered hydroxyapatite films which promote osteointegration and have other beneficial properties. In this work, we aim to develop methodology for the growth of hydroxyapatite films on surfaces other than bulk metallic parts using a wet chemical coating process, and we provide a detailed characterisation of the coatings. In this study, hydroxyapatite is grown from saturated solutions onto thin titanium films and silicon substrates and compared to results from titanium alloy substrates. The coating process efficacy is shown to be dependent on substrate roughness, hydrophilicity, and activation. The mechanism of the hydroxyapatite growth is investigated in terms of initial attachment and morphological development using SEM and XPS analysis. XPS analysis reveals the exact chemical state of the hydroxyapatite compositional elements of Ca, P, and O. The characterisation of grown hydroxyapatite layers by XRD reveals that the hydroxyapatite forms from amorphous phases, displaying preferential crystal growth along the [002] direction, with TEM imagery confirming polycrystalline pockets amid an amorphous matrix. SEM-EDX and FTIR confirmed the presence of hydroxyapatite phases through elemental atomic weight percentages and bond assignment. All data are collated and reviewed for the different substrates. The results demonstrate that once hydroxyapatite seeds, it crystallises in the same manner as bulk titanium whether that be on a titanium or silicon substrate. These data suggest that a range of substrates may be coated using this facile hydroxyapatite deposition technique, just broadening the choice of substrate for a particular function.

Synthesis and performance of a cathode catalyst derived from Bauhinia accuminata seed pods in single and stacked microbial fuel cell.

The cathode catalyst in microbial fuel cell (MFC) plays a crucial role in scaling up. Activity of biomass-derived activated carbon catalysts with appropriate precursor selection in a natural clay membrane-based MFC of 250mL was studied. The performance of scaled up MFC of 1.5L capacity with two different configurations was monitored. Rod-shaped particles with slit-type pores and amorphous graphitic nature with a surface area of 800.37m2/g was synthesized. The intrinsic doping of heteroatoms N and P in the catalyst was with atomic weight percentages of 4.5 and 3.5, respectively and the deconvolution of N1 spectra confirmed pyridinic N and graphitic N content of 17.3% and 34.1% validating its suitability as a cathode catalyst. Electrochemical characterization of the catalyst coated SS mesh electrode confirmed that a loading of 5mg/cm2 rendered higher catalytic activity compared to bare SS mesh. The maximum power density in catalyst modified cell was 0.91W/m3 compared to 0.02W/m3 as obtained in a plain stainless steel electrode cell at a COD removal efficiency of 93.3%. Series, parallel, and parallel-series combinations of 6 cells showed a maximum voltage of 4.15V when connected in series and a maximum power density of 1.54W/m3 when connected in parallel. System with multielectrode assembly achieved better power and current density (0.84W/m3 and 1.97A/m3) than the mixed parallel series circuitry (0.7W/m3 and 0.57A/m3). These performance results confirm that the catalyst is effective in both stacked and hydraulically connected system.

Influence of annealing on the properties of chemically prepared SnS thin films

Thin films of SnS were deposited chemically, and they are annealed at four different temperatures: 100 °C, 150 °C, 200 °C, and 250 °C. X-ray diffraction, Raman analysis, UV-visible spectroscopy, field emission scanning electron microscopy, and energy dispersive spectroscopy were used to investigate the impact of annealing temperature on the structural, optical, morphological, and chemical properties of thin films. As the annealing temperature rose, it was seen from the XRD patterns that the crystallinity of SnS films improved. At 250 °C, the film was almost evaporated, and the XRD pattern showed no peaks at all. The lattice strain and crystallite size were computed from the WilliamsonHall plots. The crystallite size increased and the lattice strain decreased with the increase in the annealing temperature. According to optical investigations, the samples' optical bandgap shrank as the annealing temperature rose. Morphological studies showed the formation of well-adhered films, and as the annealing temperature increased, the film became denser and more continuous with larger grains. The atomic weight percentage of sulphur decreased as the annealing temperature increased, according to the EDS analysis. Photovoltaic structures with the configuration ITO/SnS/CdS/Ag were fabricated. From the I-V characteristics, it was observed that the cell structure formed with SnS annealed at 200 °C showed better cell performance.

Development and analysis of solid lubricant coating on M2 high-speed steel using the EDC process

This paper reports solid lubricant coating on the M2 high-speed steel substrate with MoS2:Cu (50:50) green compact electrode by electric discharge coating (EDC) process. The influence of input parameters (peak current(I) and pulse duration(ton)) on the coating responses (thickness, microhardness, and surface roughness) have been investigated. The coated materials atomic weight percentage and chemical compounds are examined through EDS and XRD analysis. The maximum coating thickness (695.3μm) was reported at ton − 750 μs and I- 5 A. The coated samples microhardness exhibit between 217.8 HV—669.43 HV, which is lesser than the substrate (750 HV). The adhesive strength of the coating surface was examined using the scratch test with the progressive load. The result shows, adhesive strength increased at higher current level.

The Al3+ doped modified ZnO sensor material: Fabrication, characterization and gas sensing characteristics of some environmental pollutant and greenhouse gases

The current study examines the gas sensing properties of the fabricated material Al3+ modified ZnO. The material was fabricated by using co-precipitation technique. Here, sodium hydroxide was used as precipitating material to precipitate zinc as zinc hydroxide to convert it finally into ZnO. The insitu doping method was adapted to doped aluminum through ZnO lattice. The material was characterized by means of several characterization techniques. The X-ray diffraction (XRD) instrument utilized for structural investigation of the prepared material. The mean particle size estimated 28 nm using the Debye-Scherer equation. Scanning electron microscopy (SEM) was utilized for surface and topographic properties of the prepared material, while energy dispersive x-ray spectroscopy (EDX) was utilized to get atomic weight percentage of elements. The ultra violet diffuse reflectance spectroscopy (UV-DRS) was used to find the energy band gap of modified ZnO. The hexagonal crystal lattice of the materials was confirmed from transmission electron microscopy (TEM) analysis. Thick films of Al3+ doped ZnO made using a screen printing technology. The developed thick film sensor of Al3+ doped ZnO was utilized to sense certain harmful gases such as toluene vapors (TV), LPG, petrol vapors, CO2 and CO. The material showed considerable response for CO and LPG at 500 ppm gas concentration with 85.20% and 76.23% gas response at 90°C and 120°C respectively. The other gas sensing characteristics of the materials was also examined for the fabricated Al3+ doped ZnO sensor such as response and recovery, reusability, ppm variation and gas response. From overall study it was observed that fabricated sensor Al3+ doped ZnO is reliable, and very rapid to detect the carbon monoxide vapors and liquefied petroleum gas vapors (LPG) at moderately high temperature and low gas concentration. The built sensor’s gas sensing mechanism was assessed to detect CO and LPG.

Enhanced thermal and dielectric properties of porous thin films of graphene, conjugated terpolymer of pyrene/thiophene/heptaldehyde, and polyvinylidene difluoride alloys

We have developed conductive, lightweight, and porous composite of polyvinylidene difluoride by blending with synthesized conjugated terpolymer and graphene for conductive polymer composite applications. The new conjugated terpolymer designated as PEPy-TP is synthesized from 3,4-ethylenedioxythiophene, 1-pyrenecarboxzaldehyde, and heptaldehyde through friedel craft reaction. The synthesized terpolymer PEPy-TP have been blended with polyvinylidene difluoride and graphene nanosheets to form porous composite and has been characterized using XRD, TGA, TG-DSC, DTA, DTG, SEM, EDX, and Dielectric spectroscopy. The porous composite is comprised of varying weight percentages of (1, 3, and 5%) of GNS and 10 wt% PEPy-TP in PVDF. The thermal studies on the porous composites indicated that the decomposition occurred at a temperature around 270 and 470 °C corresponds to the PEPy-TP and PVDF/PEPy-TP/GNS (1, 3, and 5%), respectively. The EDX spectrum of neat PEPy-TP polymer and their porous composites of PVDF/PEPy-TP/GNS (1, 3, and 5%) result clearly shows the presence of all elements, such as C, O, S, and F with an atomic weight percentage also. The PVDF/PEPy-TP/5% GNS porous composites having a tremendous electrical conductivity and the dielectric constant value is 56 at 1 MHz and their conductivity of this polymer porous composites value is determined to be 4.9 × 10−6 S/cm at 100 kHz, respectively.

Evaluation of microstructure and mechanical properties of squeeze overcast Al7075−Cu composite joints

Al7075−Cu composite joints were prepared by the squeeze overcast process. The effects of melt temperature, die temperature, and squeeze pressure on hardness and ultimate tensile strength (UTS) of squeeze overcast Al7075−Cu composite joints were studied. The experimental results depict that squeeze pressure is the most significant process parameter affecting the hardness and UTS. The optimal values of UTS (48 MPa) and hardness (76 HRB) are achieved at a melt temperature of 800 °C, a die temperature of 250 °C, and a squeeze pressure of 90 MPa. Scanning electron microscopy (SEM) shows that fractured surfaces show flat-faced morphology at the optimal experimental condition. Energy-dispersive spectroscopy (EDS) analysis depicts that the atomic weight percentage of Zn decreases with an increase in melt temperature and squeeze pressure. The optimal mechanical properties of the Al7075−Cu overcast joint were achieved at the Al2Cu eutectic phase due to the large number of copper atoms that dispersed into the aluminum melt during the solidification process and the formation of strong intermetallic bonds. Gray relational analysis integrated with the Taguchi method was used to develop an optimal set of control variables for multi-response parametric optimization. Confirmatory tests were performed to validate the effectiveness of the employed technique. The manufacturing of squeeze overcast Al7075−Cu composite joints at optimal process parameters delivers a great indication to acknowledge a new method for foundry practitioners to manufacture materials with superior mechanical properties.

Mineral Nanomedicine to Enhance the Efficacy of Adjuvant Radiotherapy for Treating Osteosarcoma

It is vital to remove residual tumor cells after resection to avoid the recurrence and metastasis of osteosarcoma. In this study, a mineral nanomedicine, europium-doped calcium fluoride (CaF2:Eu) nanoparticles (NPs), is developed to enhance the efficacy of adjuvant radiotherapy (i.e., surgical resection followed by radiotherapy) for tumor cell growth and metastasis of osteosarcoma. In vitro studies show that CaF2:Eu NPs (200 μg/mL) exert osteosarcoma cell (143B)-selective toxicity and migration-inhibiting effects at a Eu dopant amount of 2.95 atomic weight percentage. These effects are further enhanced under X-ray irradiation (6 MeV, 4 Gy). Furthermore, in vivo tests show that intraosseous injection of CaF2:Eu NPs and X-ray irradiation have satisfactory therapeutic efficacy in controlling primary tumor size and inhibiting primary tumor metastasis. Overall, our results suggest that CaF2:Eu NPs with their osteosarcoma cell (143B)-selective toxicity and migration-inhibiting effects combined with radiotherapy might be nanomedicines for treating osteosarcoma after tumor resection.

Facile synthesis and electrochemical evaluation characteristics of NiO-CeO2 based inorganic nanocomposite anode material for application in LTSOFC

In this research work, we report the synthesis and characterization of NiO-Ce0.95Nd0.05O2-δ-Ce0.95Gd0.05O2-δ (NiO-CNO-CGO) nanocomposite anode material for LTSOFC. The thermal properties of NiO-CNO-CGO precursor were studied using TGA-DSC analysis which inferred that the formation of pure-phase was completed at around 600 °C. XRD analysis reveals a single fluorite cubic phase structure. FTIR data confirmed the occurrence of stretching vibration of M-O bond in the sample. Presence of nano-sized particles was confirmed by particle size analysis. The surface morphology was studied using SEM resulting in unsmooth grains. Respective atomic weight percentage of Ni, Ce, Nd, Gd and O was confirmed by EDAX studies. The surface roughness was studied using AFM. The sample resulted in a conductance of 4.55 x 10−4 Scm−1 in air atmosphere with activation energy of 0.4483 eV. The obtained results were discussed in order to use the material as an efficient anode for LTSOFC application.

Suaeda maritima (L.) Dumort GREEN SYNTHESIS- REDUCED NICKEL OXIDE NANOPARTICLES FOR ANTIOXIDANT AND BACTERICIDAL ACTIVITY

A unique way, green, cost-effective, and direct fabrication method is proposed for the synthesis of Nickel Oxide Nanoparticles (NPs) in an eco-environmentally way through leaf extract of Suaeda maritima (L.) Dumort. The nickel oxide nanoparticles were synthesized using Nickel (II) nitrate hexahydrate as a metal source and aqueous leaf extract of S. maritima was utilized as a green reducing agent. The formation of NPs was monitored by the change in color in the reaction mixture and the synthesized NPs were characterized using UV-visible spectrophotometer, Fourier Transform infrared (FT-IR) spectroscopy, field emission scanning electron microscope (FE SEM), X-ray diffractometer (XRD), and energy-dispersive X-ray spectroscopy (EDX). Further, the antibacterial activity of synthesized NPs was carried using the agar plate well diffusion method and antioxidant activity by DPPH free radical scavenging activity of the NPs was studied. The UV-visible absorption spectra of nanoparticles show a characteristic maximum absorption peak centered at 397 nm. The functional group analysis by FT-IR confirms the presence of various bio-active functional groups in the synthesized particles. The structural characterization confirms that the particles were Face Centred Cubic lattice structure having IR-regular in shape and rough surface with average atomic weight percentages of 76.3%. The synthesized nanoparticles were found to be potent against the growth of gram-positive (Bacillus subtilis, Staphylococcus aureus) and gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. In the DPPH assay, the IC 50 values of the synthesized NPs were found to be 28.01 μg/mL which is very close to standard ascorbic acid (22.19 μg/mL) whereas the IC 50 of the aqueous plant leaf extract was found to be 47.30 μg/m confirms that the nanoparticles having enhanced antioxidant activity. From the results of the study it can be concluded that this protocol is simple, rapid, one step, eco-friendly, non-toxic for the synthesis of nickel nanoparticles.

Signature Of stiffness transition in electrical behaviour of Se-Te-Sn-Ge glassy alloys

ABSTRACT In the family of amorphous semiconductors, non-oxide chalcogenide glasses (ChGs) are in the spotlight because of their widespread applications in various scientific and industrial fields. In this paper, we have studied thermally activated A.C. conduction in multi-component Se-Te-Sn-Ge (STSG) glassy alloys in bulk form at different audio frequencies. The activation energy of A.C. conductivity and other electrical parameters have also been calculated to explore the material’s conduction mechanism. The A.C. conductivity σac is found proportional to ωs where ω is the angular frequency. The frequency exponent s is found to decrease with increasing temperature, which is in agreement with the correlation barrier hopping (CBH) model. The variation of the A.C. conduction with temperature and frequency of the glasses has been studied. Their microstructure has also been studied using the XRD characterisation technique to explore their electrical transport properties. XRD patterns confirm the glassy nature of the as-prepared samples. The change in behaviour of various electrical parameters after 2 atomic weight percentages of Ge indicates the occurrence of a stiffness transition followed by a self-organisation of the corner-sharing and the edge-sharing arrangements of the GeSe4 phase.

Facile Soft Chemical Synthesis and Physical Characterization of Aluminum Doped CeO2 Nanoparticles for Multiple Applications

In this work, a simple facile preparation of Ce1-xAlxO2-δ (where x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5) nanoparticles by chemical synthesis route is reported. In the preparation, appropriate quantities of metal nitrate salts were dissolved in water alongwith required amount of sodium hydroxide as precipitant. The resultant precipitate mixture [Ce(OH)3 + Al(OH)3] was washed with water, filtered, dried and heat treated to get the phase pure Al doped CeO2 nanoparticles. The synthesized oxide materials were characterized by XRD, FTIR, particle size analysis, SEM and EDAX to understand their structural, functional and particle properties. The XRD patterns revealed the presence of cubic (FCC) crystalline structure in the samples. The presence of Al-O and Ce-O stretching mode of vibration was confirmed by FTIR analysis. The particle size of the materials was found in the range of 117.23 to 257.06 nm. Presence of nano and micron sized grains was noticed by SEM photographs. EDAX confirmed the presence of appropriate atomic weight percentage of elements in the samples. The results suggested that the prepared Al doped ceria nanoparticles can be useful in several applications.

Tuning the Threshold Voltage of a SnO2 Nanowire Transistor Through Microwave-assisted Metal-oxide Reduction

Numerous studies have suggested that n-type semiconductor nanowires provide excellent electrical properties, as well as notable mechanical flexibility, to electronic devices. However, the dynamic threshold voltages of these devices significantly reduce our ability to produce robust and stable transistors consistently. In this study, tuning of the threshold voltage (Vth) of a SnO2 nanowire transistor was investigated by using a household microwave oven to control the oxygen vacancies on the surface of the SnO2 nanowire. The extent of the negative shift in the Vth of the SnO2 nanowire transistor was controlled by varying the applied power and time of the microwave irradiation in the atomic weight percentage of oxygen on the SnO2 nanowire’s surface. A Vth shift of −0.42 ± 0.69 to −4.25 ± 0.52 V was observed when the applied power was varied from 200 to 1000 W while a shift of −0.46 ± 0.27 to −9.87 ± 0.67 V occurred for microwave irradiation times of 20 to 80 s. Thus, the Vth could be tuned over a wide range by controlling the irradiation time while it could be fine-tuned using the applied power. The Vth characteristics of the controlled SnO2 nanowire transistors were monitored over 20 days in a normal atmosphere and were observed to remain unchanged. Notably, these characteristics were achieved without the application of an additional passivation layer. This method, which is simpler and more effective than other existing methods, can be readily applied for the production of SnO2 nanowire transistors.