scholarly journals A Flexible Piezoelectric Nanogenerator Based on Aligned P(VDF-TrFE) Nanofibers

Micromachines ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 302 ◽  
Author(s):  
Sujian You ◽  
Lingling Zhang ◽  
Jinzheng Gui ◽  
Heng Cui ◽  
Shishang Guo
Keyword(s):  
Short Circuit ◽  
Short Circuit Current ◽  
Maximum Output ◽  
Rotating Drum ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Β Phase ◽  
Self Powered ◽  
Uniform Diameter

Aligned P(VDF-TrFE) nanofibers are successfully fabricated by advanced electrospinning. The aligned feature of the nanofibers is achieved by using parallel electrodes, which is fabricated by lithography and wet etching, and a rotating drum collector. Scanning electron microscope (SEM) images show that the nanofibers are highly ordered with a smooth surface and uniform diameter. X-ray diffraction (XRD) and Fourier Transform Infrared spectrum (FTIR) tests indicate that the fibers contain high β phase content. The nanogenerator based on aligned P(VDF-TrFE) nanofibers exhibits good electric performance with a maximum output voltage as high as 12 V and peak-peak short circuit current about 150 nA, highlighting the potential application of P(VDF-TrFE) on self-powered and wearable devices.

scholarly journals Photocurrent density and electrical properties of Bi0.5Na0.5TiO3-BaNi0.5Nb0.5O3 ceramics

2021 ◽  
Author(s):  
Mingqiang Zhong ◽  
Qin Feng ◽  
Changlai Yuan ◽  
Xiao Liu ◽  
Baohua Zhu ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Photovoltaic Effect ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Photocurrent Density ◽  
Open Circuit ◽  
Light Conditions ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
X Ray

AbstractIn this work, the (1−x)Bi0.5Na0.5TiO3-xBaNi0.5Nb0.5O3 (BNT-BNN; 0.00 ⩽ x ⩽ 0.20) ceramics were prepared via a high-temperature solid-state method. The crystalline structures, photovoltaic effect, and electrical properties of the ceramics were investigated. According to X-ray diffraction, the system shows a single perovskite structure. The samples show the normal ferroelectric loops. With the increase of BNN content, the remnant polarization (Pr) and coercive field (Ec) decrease gradually. The optical band gap of the samples narrows from 3.10 to 2.27 eV. The conductive species of grains and grain boundaries in the ceramics are ascribed to the double ionized oxygen vacancies. The open-circuit voltage (Voc) of ∼15.7 V and short-circuit current (Jsc) of ∼1450 nA/cm2 are obtained in the 0.95BNT-0.05BNN ceramic under 1 sun illumination (AM1.5G, 100 mW/cm2). A larger Voc of 23 V and a higher Jsc of 5500 nA/cm2 are achieved at the poling field of 60 kV/cm under the same light conditions. The study shows this system has great application prospects in the photovoltaic field.

Fabrication of TiO2 Nanotubes Array by Anodization for DSSC

2013 ◽  
Vol 743-744 ◽  
pp. 920-925
Author(s):  
Hong Zhou Yan ◽  
Jun You Yang ◽  
Shuang Long Feng ◽  
Ming Liu ◽  
Jiang Ying Peng ◽  
...  
Keyword(s):  
Fill Factor ◽  
Open Circuit Voltage ◽  
Short Circuit ◽  
Photovoltaic Performance ◽  
Short Circuit Current ◽  
Short Circuit Current Density ◽  
Open Circuit ◽  
Tetrabutyl Titanate ◽  
X Ray Diffraction ◽  
X Ray

TiO2 nanotubes array was fabricated by anodization. Effect of reaction duration on the morphology of TiO2 nanotube arrays was studied detailedly. The structure and morphology of the prepared nanotubes array was characterized by X-ray diffraction and scanning electron microscopy, respectively. The fabricated TiO2 arrays were peeled off and adhered to FTO glass with adhesive (mixture of tetrabutyl titanate and polyethylene glycol), then they were sintered at 450 for photoanode of DSSC. The photovoltaic performance of the prepared sample as the DSSC anode was investigated. An open circuit voltage of 0.69V and a short circuit current density of 7.78mA/cm2 were obtained, and the fill factor and the convert efficiency were 0.517 and 2.78%, respectively.

Analysis of Strain Compensation in Quantum Dot Embedded GaAs Solar Cells

2007 ◽  
Vol 1031 ◽  
Author(s):  
Christopher Bailey ◽  
Cory Cress ◽  
Ryne Raffaelle ◽  
Seth Hubbard ◽  
William Maurer ◽  
...  
Keyword(s):  
Solar Cell ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Open Circuit ◽  
X Ray Diffraction ◽  
Solar Cell Performance ◽  
X Ray ◽  
Force Microscopy ◽  
Transmission Electron ◽  
Strain Compensation

AbstractThe effects of strain within stacked layers of InAs quantum dots (QDs) were investigated. InAs QD test structures with and without strain compensation (SC) were analyzed using atomic force microscopy, transmission electron microscopy, and X-ray diffraction. The affects of strain compensation on test structure morphology and on GaAs-based QD solar cell performance was studied as a function of the thickness of the SC layer. X-ray diffraction analysis of the QD embedded test structures reveals a relationship between the SC thickness and the observed crystalline quality. Air mass zero illuminated current vs. voltage data and spectral responsivity measurements were used for the solar cell comparison. When SC is employed, QD insertion shows a lower open circuit voltage, in reference to a baseline device without QDs, but leads to an enhancement in the short circuit current of the device.

scholarly journals Dependence of material properties and photovoltaic performance of triple cation tin perovskites on the iodide to bromide ratio

2019 ◽  
Vol 150 (11) ◽  
pp. 1921-1927 ◽  
Author(s):  
Stefan Weber ◽  
Thomas Rath ◽  
Birgit Kunert ◽  
Roland Resel ◽  
Theodoros Dimopoulos ◽  
...  
Keyword(s):  
Material Properties ◽  
Fill Factor ◽  
Open Circuit Voltage ◽  
Short Circuit ◽  
Photovoltaic Performance ◽  
Short Circuit Current ◽  
Short Circuit Current Density ◽  
Open Circuit ◽  
X Ray Diffraction ◽  
X Ray

Abstract In this work, the influence of a partial introduction of bromide (x = 0–0.33) into MA0.75FA0.15PEA0.1Sn(BrxI1−x)3 (MA: methylammonium, FA: formamidinium, PEA: phenylethylammonium) triple cation tin perovskite on the material properties and photovoltaic performance is investigated and characterized. The introduction of bromide shifts the optical band gap of the perovskite films from 1.29 eV for the iodide-based perovskite to 1.50 eV for the perovskite with a bromide content of x = 0.33. X-ray diffraction measurements reveal that the size of the unit cell is also gradually reduced based on the incorporation of bromide. Regarding the photovoltaic performance of the perovskite films, it is shown that already small amounts of bromide (x = 0.08) in the perovskite system increase the open circuit voltage, short circuit current density and fill factor. The maximum power conversion efficiency of 4.63% was obtained with a bromide content of x = 0.25, which can be ascribed to the formation of homogeneous thin films in combination with higher values of the open circuit voltage. Upon introduction of a higher amount of bromide (x = 0.33), the perovskite absorber layers form pinholes, thus reducing the overall device performance. Graphic abstract

Mechanical Alloying Behavior in the Nb-Si, Ta-Si, and Nb-Ta-Si Systems

1988 ◽  
Vol 133 ◽  
Author(s):  
K. S. Kumar ◽  
S. K. Mannan
Keyword(s):  
High Temperature ◽  
Mechanical Alloying ◽  
Mechanical Milling ◽  
Room Temperature ◽  
Crystalline Compound ◽  
X Ray Diffraction ◽  
X Ray ◽  
Β Phase ◽  
Α Phase

ABSTRACTThe mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.

scholarly journals Hydrochloric Acid Modification and Lead Removal Studies on Naturally Occurring Zeolites from Nevada, New Mexico, and Arizona

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1238
Author(s):  
Garven M. Huntley ◽  
Rudy L. Luck ◽  
Michael E. Mullins ◽  
Nick K. Newberry
Keyword(s):  
New Mexico ◽  
Surface Area ◽  
Bet Surface Area ◽  
Lead Removal ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Naturally Occurring ◽  
27Al Mas Nmr ◽  
Modified Zeolites

Four naturally occurring zeolites were examined to verify their assignments as chabazites AZLB-Ca and AZLB-Na (Bowie, Arizona) and clinoptilolites NM-Ca (Winston, New Mexico) and NV-Na (Ash Meadows, Nevada). Based on powder X-ray diffraction, NM-Ca was discovered to be mostly quartz with some clinoptilolite residues. Treatment with concentrated HCl (12.1 M) acid resulted in AZLB-Ca and AZLB-Na, the chabazite-like species, becoming amorphous, as confirmed by powder X-ray diffraction. In contrast, NM-Ca and NV-Na, which are clinoptilolite-like species, withstood boiling in concentrated HCl acid. This treatment removes calcium, magnesium, sodium, potassium, aluminum, and iron atoms or ions from the framework while leaving the silicon framework intact as confirmed via X-ray fluorescence and diffraction. SEM images on calcined and HCl treated NV-Na were obtained. BET surface area analysis confirmed an increase in surface area for the two zeolites after treatment, NM-Ca 20.0(1) to 111(4) m2/g and NV-Na 19.0(4) to 158(7) m2/g. 29Si and 27Al MAS NMR were performed on the natural and treated NV-Na zeolite, and the data for the natural NV-Na zeolite suggested a Si:Al ratio of 4.33 similar to that determined by X-Ray fluorescence of 4.55. Removal of lead ions from solution decreased from the native NM-Ca, 0.27(14), NV-Na, 1.50(17) meq/g compared to the modified zeolites, 30 min HCl treated NM-Ca 0.06(9) and NV-Na, 0.41(23) meq/g, and also decreased upon K+ ion pretreatment in the HCl modified zeolites.

scholarly journals Electrospun Membranes Based on Polycaprolactone, Nano-Hydroxyapatite and Metronidazole

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 931
Author(s):  
Ioana-Codruţa Mirică ◽  
Gabriel Furtos ◽  
Ondine Lucaciu ◽  
Petru Pascuta ◽  
Mihaela Vlassa ◽  
...  
Keyword(s):  
Fiber Diameter ◽  
Maximum Load ◽  
Guided Bone Regeneration ◽  
Attenuated Total Reflectance ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Total Reflectance ◽  
X Ray ◽  
Electrospun Membranes

The aim of this research was to develop new electrospun membranes (EMs) based on polycaprolactone (PCL) with or without metronidazole (MET)/nano-hydroxyapatite (nHAP) content. New nHAP with a mean diameter of 34 nm in length was synthesized. X-ray diffraction (XRD) and attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR) were used for structural characterization of precursors and EMs. The highest mechanical properties (the force at maximum load, Young’s modulus and tensile strength) were found for the PCL membranes, and these properties decreased for the other samples in the following order: 95% PCL + 5% nHAP > 80% PCL + 20% MET > 75% PCL + 5% nHAP + 20% MET. The stiffness increased with the addition of 5 wt.% nHAP. The SEM images of EMs showed randomly oriented bead-free fibers that generated a porous structure with interconnected macropores. The fiber diameter showed values between 2 and 16 µm. The fiber diameter increased with the addition of nHAP filler and decreased when MET was added. New EMs with nHAP and MET could be promising materials for guided bone regeneration or tissue engineering.

scholarly journals A Self-Powered Nanogenerator for the Electrical Protection of Integrated Circuits from Trace Amounts of Liquid

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhuang Hui ◽  
Ming Xiao ◽  
Daozhi Shen ◽  
Jiayun Feng ◽  
Peng Peng ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
High Performance ◽  
Printed Circuit Board ◽  
Short Circuit ◽  
High Sensitivity ◽  
Short Circuit Current ◽  
Fast Response ◽  
Open Circuit ◽  
Circuit Board ◽  
Self Powered

Abstract With the increase in the use of electronic devices in many different environments, a need has arisen for an easily implemented method for the rapid, sensitive detection of liquids in the vicinity of electronic components. In this work, a high-performance power generator that combines carbon nanoparticles and TiO2 nanowires has been fabricated by sequential electrophoretic deposition (EPD). The open-circuit voltage and short-circuit current of a single generator are found to exceed 0.7 V and 100 μA when 6 μL of water was applied. The generator is also found to have a stable and reproducible response to other liquids. An output voltage of 0.3 V was obtained after 244, 876, 931, and 184 μs, on exposure of the generator to 6 μL of water, ethanol, acetone, and methanol, respectively. The fast response time and high sensitivity to liquids show that the device has great potential for the detection of small quantities of liquid. In addition, the simple easily implemented sequential EPD method ensures the high mechanical strength of the device. This compact, reliable device provides a new method for the sensitive, rapid detection of extraneous liquids before they can impact the performance of electronic circuits, particularly those on printed circuit board.

STRUCTURAL AND ELECTROCHEMICAL PROPERTIES OF THIN LAYERS OF BINARY Ni–Fe ALLOYS ELECTRODEPOSITED BY TWO DIFFERENT BATHS: ACID AND IONIC LIQUID

2018 ◽  
Vol 25 (08) ◽  
pp. 1950025
Author(s):  
RAFIK MAIZI ◽  
ATHMANE MEDDOUR ◽  
CÉLINE ROUSSE
Keyword(s):  
Ionic Liquid ◽  
Nickel Content ◽  
Deposition Potential ◽  
Thin Layers ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Different Shapes ◽  
Fe Alloys ◽  
Irregular Behavior

The deposition of Ni–Fe thin layers in boric acid and ionic liquid ([BuMePyr][Tf2N]) baths were successfully prepared. The obtained materials have been characterized by X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX) and SEM. Meanwhile, these materials were carried out by chronoamperometry or chronopotentiometry by varying the intensity of the current and the deposition potential. The results indicate that the coatings of Ni–Fe alloys were successfully obtained by electroplating on the copper substrates, and the alloys composition shows irregular behavior with polarization. The nickel content in the samples is in the range of 55–90%, but the iron content ranges from 10–30%, when potential deposits were varied from [Formula: see text]2[Formula: see text]V to [Formula: see text]4[Formula: see text]V vs Ni electrode. The results also showed that the thin layers are monophased; they contain the Ni3Fe phase. Further, SEM images of Ni–Fe alloys show the different shapes of particles.

scholarly journals Influence of pretreatment on the properties of α-Fe2O3 and the effect on photocatalytic degradation of methylene blue under visible light

2020 ◽  
Vol 82 (11) ◽  
pp. 2415-2424
Author(s):  
S. Mokhtari ◽  
N. Dokhan ◽  
S. Omeiri ◽  
B. Berkane ◽  
M. Trari
Keyword(s):  
Methylene Blue ◽  
Average Crystallite Size ◽  
Sample Surface ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Lattice Constants ◽  
Electrochemical Pretreatment ◽  
Crystal Properties ◽  
Rhombohedral Symmetry

Abstract The hematite (α-Fe2O3) nanostructures were synthesized by thermal oxidation of metal at 500 °C under atmospheric pressure. We studied the effect of the electrochemical pretreatment of the substrate before calcinations and its impact on the morphology, crystalline structure, lattice microstructural, and optical properties of α-Fe2O3. Uniform nanosheets were observed on the sample surface after calcination; their dimension and morphology were accentuated by the pretreatment, as confirmed by the SEM images. The characteristics of the nanostructures, analyzed by X-ray diffraction (XRD), revealed a rhombohedral symmetry with the space group R-3c and lattice constants: a = 0.5034 nm and c = 1.375 nm. The average crystallite size and strain, determined from the Williamson-Hall (W-H) plot, showed substantial variations after the substrate pretreatment. The Raman spectroscopy confirmed the changes in the crystal properties of the hematite submitted to pretreatment. The diffuse reflectance allowed to evaluate the optical gap which lies between 1.2 and 1.97 eV, induced by the electrochemical processing. The photocatalytic activity of α-Fe2O3 films was assessed by the degradation of methylene blue (MB) under LED light; 15% enhancement of the degradation for the pretreated specimens was noticed.

Sign in / Sign up

Export Citation Format

Share Document