scholarly journals Designing and Synthesis of (Cd2+, Li+), Cr3+, Bi3+ Doped CePO4 Materials Optical, Electrochemical, Ionic Conductivity Analysis

2020 ◽  
Author(s):  
Salah Kouass ◽  
Amor Fadhalaoui ◽  
Hassouna Dhaouadi ◽  
Fathi Touati
Keyword(s):  
Ionic Conductivity ◽  
Metal Ion ◽  
Energy Gap ◽  
Cycling Performance ◽  
Total Conductivity ◽  
Electrochemical Tests ◽  
Total Electrical Conductivity ◽  
Ion Doping ◽  
Different Temperatures ◽  
First Time

Most of the work has been done on the optical properties of the rare earth doped CePO4, so there are few studies on the effect of metal ion doping on CePO4. The doping improves the properties of the compounds and can lead to new properties. It is the first time, that multi- ionic doping process is used in the CePO4matrix, in order to improve the ionic conductivity and the electrochemical stability. The low percentage of (Cd2+, Li+), Cr3+, Bi3+ dopant affect the structure showing a weak decrease in the lattice parameters compared to the CePO4. Impedance spectroscopy analysis was used to analyze the electrical behavior of samples as a function of frequency at different temperatures. The total electrical conductivity plots obtained from impedance spectra shows an increase of the total conductivity as Li, Cr-content increases. The determined energy gap values decrease with increasingly Li+, Cr3+ and Bi3+ doping content. Electrochemical tests showed an improved capacity when increasing the Li+, Cr3+ and Bi3+ content and a stable cycling performance.

A Study of the Photoluminescence and Reflectivity Spectra of MOCVD Grown MnSe

1994 ◽  
Vol 340 ◽  
Author(s):  
M. Di Blasio ◽  
L. Aigouy ◽  
M. Averous ◽  
J. Calas ◽  
P. Tomasini ◽  
...  
Keyword(s):  
Energy Gap ◽  
Stokes Shift ◽  
Thin Layers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zinc Blende ◽  
Reflectivity Spectra ◽  
Different Temperatures ◽  
First Time ◽  
Zinc Blende Structure

Photoluminescence (PL) experiments at 2K are performed on MOCVD grown MnSe. The precursors used in the growth stage are methylpentacarbonylmanganese and diethylselenide. Pyrolysis of the percursors is realized inside a gradient reactor under a constant H2 flux, between 280-55°TC. The compound is epitaxially grown on various substrates (Si, InP, GaSb, GaAs, ZnTe/GaAs, etc.). On some of these samples the compound presents a zinc blende structure, while in the other samples rock salt formation has been identified. The first substrate is used because of its interest in Si technology, while the others are used because MnSe can be grown in the zinc blende phase for very thin layers. For the first time x-ray diffraction data has allowed us to determine the lattice constant of zincblende MnSe (aMnse (oct)=5.818Å), confirming the close approximation (a ∼ 5.9Å) used from the Zn1-xMnxSe alloy. These compounds have visible Mn++ transitions at 2.12-5eV; other features are also visible at 2.3-4, 2.7, and 3.0eV. The energy gap transition of tetrahedral thin film layers of MnSe is seen for the first time in PL spectra. A temperature dependant PL study is performed on MnSe in the 2-200K range. Reflectivity experiments are used to attempt to identify the internal manganese transitions. A qualitative PL analysis of the samples grown at different temperatures and on different substrates is provided. A Stokes shift is encountered when the results are compared.

An imidazopyrazine-derived anion for lithium conducting electrolyte application

RSC Advances ◽  
2015 ◽  
Vol 5 (123) ◽  
pp. 101917-101922 ◽  
Author(s):  
Leszek Niedzicki ◽  
Jędrzej Korczak ◽  
Anna Bitner ◽  
Maria Bukowska ◽  
Przemyslaw Szczecinski
Keyword(s):  
Ionic Conductivity ◽  
Transference Number ◽  
Cycling Performance ◽  
High Ionic Conductivity ◽  
First Time

Synthesized for the first time, a LiTDPI salt in EC : DMC (1 : 2) was tested as a lithium conducting electrolyte and it showed high ionic conductivity, a high lithium transference number and a good cycling performance.

scholarly journals Stabilization of Li0.33La0.55TiO3 Solid Electrolyte Interphase Layer and Enhancement of Cycling Performance of LiNi0.5Co0.3Mn0.2O2 Battery Cathode with Buffer Layer

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 989
Author(s):  
Feihu Tan ◽  
Hua An ◽  
Ning Li ◽  
Jun Du ◽  
Zhengchun Peng
Keyword(s):  
Solid State ◽  
Ionic Conductivity ◽  
Solid Electrolyte ◽  
Buffer Layer ◽  
Solid Electrolyte Interphase ◽  
Cycling Performance ◽  
Physical Contact ◽  
Initial State ◽  
Amorphous Sio2 ◽  
Current Output

All-solid-state batteries (ASSBs) are attractive for energy storage, mainly because introducing solid-state electrolytes significantly improves the battery performance in terms of safety, energy density, process compatibility, etc., compared with liquid electrolytes. However, the ionic conductivity of the solid-state electrolyte and the interface between the electrolyte and the electrode are two key factors that limit the performance of ASSBs. In this work, we investigated the structure of a Li0.33La0.55TiO3 (LLTO) thin-film solid electrolyte and the influence of different interfaces between LLTO electrolytes and electrodes on battery performance. The maximum ionic conductivity of the LLTO was 7.78 × 10−5 S/cm. Introducing a buffer layer could drastically improve the battery charging and discharging performance and cycle stability. Amorphous SiO2 allowed good physical contact with the electrode and the electrolyte, reduced the interface resistance, and improved the rate characteristics of the battery. The battery with the optimized interface could achieve 30C current output, and its capacity was 27.7% of the initial state after 1000 cycles. We achieved excellent performance and high stability by applying the dense amorphous SiO2 buffer layer, which indicates a promising strategy for the development of ASSBs.

scholarly journals Natural Coatings on Titanium Surfaces to Improve Their Biological Response

2020 ◽  
Vol 2 (1) ◽  
pp. 18
Author(s):  
Sara Ferraris ◽  
Enrica Verné ◽  
Gissur Örlygsson ◽  
Paulo Tambasco ◽  
Felipe Perraro Sehn ◽  
...  
Keyword(s):  
Natural Products ◽  
Metal Ion ◽  
Antibacterial Properties ◽  
Biological Response ◽  
Aqueous Environment ◽  
Natural Substances ◽  
Ion Doping ◽  
Keratin Fibers ◽  
Scratch Tests ◽  
Titanium Substrates

Biomolecules and extracts from natural products are gaining increasing interest due to their beneficial properties for human health, low toxicity, environmental compatibility and sustainability. In this work, keratin, chitosan and peppermint essential oil have been used for the preparation of coatings on titanium substrates for biomedical implants/devices. All these coatings were obtained from local natural products/byproducts: keratin from discarded wool, chitosan from shrimp shells and peppermint essential oils from a local production. The above cited molecules were selected for their ability to stimulate soft tissue adhesion (keratin), anti-inflammatory activity (chitosan) and antibacterial activity (keratin after metal ion doping, chitosan and mint oil). The coatings were characterized by means of SEM-EDS, FTIR, zeta potential, wettability, tape and scratch tests, and cell and bacteria cultures. The coatings were successfully obtained for all the considered natural substances with good adhesion to the titanium substrates. All the coatings are chemically stable in water and the continuous coatings are mechanically resistant and protective for the metallic substrates. The keratin coatings are hydrophilic while the mint oil and chitosan coatings are hydrophobic; nanofibers, instead of continuous coatings, behave as more hydrophobic. At the physiological pH, the keratin and mint oil coatings are negatively charged when in contact with an aqueous environment, while the chitosan ones are positively charged. The oriented keratin fibers are able to drive fibroblast alignment. The Ag-doped keratin fibers and mint coating show antibacterial properties.

Polyvinyl fibers as outperform candidature in the solid polymer electrolytes

2020 ◽  
pp. 152808372097062
Author(s):  
Muhammad Yameen Solangi ◽  
Umair Aftab ◽  
Muhammad Ishaque ◽  
Aqeel Bhutto ◽  
Ayman Nafady ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Ionic Conductivity ◽  
Polymer Electrolytes ◽  
Vital Role ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Main Challenge ◽  
Different Temperatures ◽  
Solution Cast

Solid polymer electrolytes (SPEs) are the best choice to replace liquid electrolytes in supercapacitors, fuel cells, solar cells and batteries. The main challenge in this filed is the ionic conductivity and thermal stability of SPEs which is still not up to mark, therefore more investigations are needed to address these issues. In this study, PVA/salt based SPEs was fabricated using both solution cast and electro-spinning methods to probe the effect of different salts such as (NaCl, KCl and KI) and their concentrations on the ionic conductivity. Scanning electron microscopy (SEM) x and Fourier Transform Infra-Red (FTIR) have been employed to study the morphology as well as the different functional groups of SPEs, respectively. It was noted that small addition of NaCl, KCl and KI salts in SPEs dramatically increased the ionic conductivity to 5.95×10−6, 5.31×10−6 and 4.83×10−6 S/cm, respectively. Importantly, the SPEs obtained with NaCl via electro-spinning have higher ionic conductivity (5.95×10−6 S/cm) than their casted SPEs (1.87×10−6 S/cm). Thermal stability was also studied at two different temperatures i.e. 80 °C and 100 °C. The weight loss percentage of electrospun SPEs have zero percent weight loss than the solution based SPEs. The combined results clearly indicated that the nature of salt, concentration and fabrication process play a vital role in the ionic conductivity. Also, the NaCl salt with low molecular weight at low concentrations shows an enhanced ionic conductivity.

Experimental Study of Transition Metal Ion Doping on TiO2 with Photocatalytic Behavior

2014 ◽  
Vol 14 (8) ◽  
pp. 6337-6341 ◽  
Author(s):  
K. S. Siddhapara ◽  
D. V. Shah
Keyword(s):  
Experimental Study ◽  
Transition Metal ◽  
Metal Ion ◽  
Transition Metal Ion ◽  
Ion Doping

Growth Mechanism and Electrochemical Properties of Porous Hollow Tin Dioxide Nanospheres

NANO ◽  
2015 ◽  
Vol 10 (06) ◽  
pp. 1550087 ◽  
Author(s):  
Youwen Yang ◽  
Dongming Ma ◽  
Ting Cheng ◽  
Yuanhao Gao ◽  
Guanghai Li
Keyword(s):  
Growth Mechanism ◽  
Tin Dioxide ◽  
Ostwald Ripening ◽  
Lithium Ion ◽  
Average Diameter ◽  
Reversible Capacity ◽  
Cycling Performance ◽  
Experimental Conditions ◽  
Electrochemical Tests ◽  
Hydrolysis Method

Porous hollow SnO 2 nanospheres were prepared by means of enforced Sn 2+ hydrolysis method under hydrochloric acid medium. These hollow nanospheres with an average diameter of 220nm had a very thin shell thickness of about 40nm and were surrounded by elongated octahedral-like nanoparticles with the apex oriented outside. The experimental conditions, such as HCl content, reaction temperature and time directly dominated the morphology, structure and crystallinity of the obtained samples. A pre-oxidation-nucleation-growth mechanism and inside-out Ostwald-ripening method was proposed on the basis of the previous research and time-dependent experiments. Electrochemical tests showed that the porous hollow SnO 2 nanospheres exhibited improved cycling performance for anode materials of lithium-ion batteries, which retained a high reversible capacity of 540.0mAhg-1, and stable cyclic retention at 120th cycle.

scholarly journals Effect of Mn Content and Solution Annealing Temperature on the Corrosion Resistance of Stainless Steel Alloys

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Ihsan-ul-Haq Toor
Keyword(s):  
Corrosion Resistance ◽  
Annealing Temperature ◽  
Electrochemical Impedance ◽  
Austenitic Stainless Steels ◽  
Electrochemical Tests ◽  
Linear Polarization Resistance ◽  
Ni Content ◽  
Different Temperatures ◽  
Acidic Chloride ◽  
Mn Content

The corrosion behavior of two specially designed austenitic stainless steels (SSs) having different Nickel (Ni) and Manganese (Mn) contents was investigated. Prior to electrochemical tests, SS alloys were solution-annealed at two different temperatures, that is, at 1030°C for 2 h and 1050°C for 0.5 h. Potentiodynamic polarization (PD) tests were carried out in chloride and acidic chloride, whereas linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) was performed in 0.5 M NaCl solution at room temperature. SEM/EDS investigations were carried out to study the microstructure and types of inclusions present in these alloys. Experimental results suggested that the alloy with highest Ni content and annealed at 1050°C/0.5 hr has the highest corrosion resistance.

Enhancing the Power Conversion Efficiency of Inverted Organic Photovoltaics with Gold Functionalized Reduced Graphene Oxide

2015 ◽  
Vol 1737 ◽  
Author(s):  
Rebecca Isseroff ◽  
Zhenhua Yang ◽  
Jessica Kim ◽  
Andrew Chen ◽  
Miriam Rafailovich
Keyword(s):  
Graphene Oxide ◽  
Fermi Level ◽  
Reduced Graphene Oxide ◽  
Active Layer ◽  
Energy Gap ◽  
Power Conversion ◽  
Design Phase ◽  
Reduced Graphene ◽  
Exciton Recombination ◽  
First Time

ABSTRACTIn this study, an “inverted” design, phase-separated morphology and gold-functionalized reduced graphene oxide (Au-rGO) were used to address exciton recombination and poor Fermi level alignment. To increase efficiencies, a unique methodology was used to coat Au-rGO on top of the active layer. When 0.05 Au-rGO was blended with the active layer, there were metal-thiolate bonds with P3HT and π-π stacking with PCBM. However, KPFM, measured for the first time for this material, showed that the while 0.05mM Au-rGO reduced the energy gap between P3HT and PBCM, this was offset by recombination. KPFM showed that Au-rGO may be better suited between the active layer and electrode. When 0.5mM Au-rGO was coated on top of the active layer, efficiency increased (p<0.002) nearly 600%, suggesting that Au-rGO is a more effective acceptor than a constituent of the active layer.

scholarly journals Effect of metal ion doping on the photocatalytic activity of aluminophosphates

2010 ◽  
Vol 122 (5) ◽  
pp. 771-785 ◽  
Author(s):  
Avijit Kumar Paul ◽  
Manikanda Prabu ◽  
Giridhar Madras ◽  
Srinivasan Natarajan
Keyword(s):  
Photocatalytic Activity ◽  
Metal Ion ◽  
Ion Doping
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