Factors Affecting Ion Transport in Fast-Ion Conductivity Solids

1992 ◽  
Vol 293 ◽  
Author(s):  
E. A. Secco
Keyword(s):  
Ionic Conductivity ◽  
Charge Carrier ◽  
Dominant Role ◽  
Vital Role ◽  
Charge Carrier Concentration ◽  
Structural Factors ◽  
Structure Property ◽  
Factors Affecting ◽  
Ion Size ◽  
Fast Ion

AbstractFast-ion conduction in solids is considered a paradigm for structure-property relation where ionic conductivity σ = nqµ, n the concentration of charge carrier q, and µ. the mobility of the carrier. The critical conductivity determining factor, ceteris paribus, is the carrier mobility which depends on the geometry of anion array and structure in the solid. Factors inherent in the structural framework include “free” volume, “bottleneck” size, lattice disorder, etc. Other non-structural factors that can play a vital role, even a dominant role, in enhancing ionic conductivity are charge carrier concentration, ion-ion interactions or bonding characteristics, vibrational amplitudes of neighboring ions, lattice compressibility or resiliency, rotational motion of anions, ion size, etc. Many aspects of these factors will be examined in the light of recent studies and the results on some isostructural and isomorphous sulfates and other related structures to evaluate their relative contributions.

scholarly journals Strategies for fast ion transport in electrochemical capacitor electrolytes from diffusion coefficients, ionic conductivity, viscosity, density and interaction energies based on HSAB theory

RSC Advances ◽  
2017 ◽  
Vol 7 (24) ◽  
pp. 14528-14535 ◽  
Author(s):  
Morihiro Saito ◽  
Satoru Kawaharasaki ◽  
Kensuke Ito ◽  
Shinya Yamada ◽  
Kikuko Hayamizu ◽  
...  
Keyword(s):  
Ionic Conductivity ◽  
Ion Transport ◽  
Propylene Carbonate ◽  
Diffusion Coefficients ◽  
Electrochemical Capacitor ◽  
Interaction Energies ◽  
Factors Affecting ◽  
Fast Ion ◽  
Hsab Theory

To elucidate factors affecting ion transport in capacitor electrolytes, five propylene carbonate (PC) electrolytes were prepared, each of which includes a salt ((C2H5)4NBF4, (C2H5)4NPF6, (C2H5)4NSO3CF3, (C2H5)3CH3NBF4 and LiBF4).

RESTRICTIONS OF EXTENSIVE PRODUCTION TO ENSURE FOOD SECURITY IN CHINA

2020 ◽  
Author(s):  
L. Li ◽  
Keyword(s):  
Food Security ◽  
Food Production ◽  
Agricultural Development ◽  
Science And Technology ◽  
Vital Role ◽  
Food Insufficiency ◽  
Factors Affecting ◽  
Agricultural Mechanization

Being over-dependent on imports, China has been faced with the problem of food insufficiency in recent years.This paper, with the adoption of the indicators of agricultural development and relevant models, aims to explore factors affecting food security in China, in particular, technological elements. The findings demonstrate that technology plays a vital role in improving food production. It is recommended to increase the input of science and technology and improve agricultural mechanization.

Under Pressure: Mechanochemical Effects on Structure and Ion Conduction in the Sodium-Ion Solid Electrolyte Na3PS4

2020 ◽  
Author(s):  
Theodosios Famprikis ◽  
O. Ulas Kudu ◽  
James Dawson ◽  
Pieremanuele Canepa ◽  
François Fauth ◽  
...  
Keyword(s):  
Ionic Conductivity ◽  
Mechanochemical Synthesis ◽  
Activation Volume ◽  
External Pressure ◽  
Sodium Ion ◽  
Variable Pressure ◽  
Ion Conductor ◽  
Ceramic Synthesis ◽  
Solid State Batteries ◽  
Fast Ion

<div> <p>Fast-ion conductors are critical to the development of solid-state batteries. The effects of mechanochemical synthesis that lead to increased ionic conductivity in an archetypical sodium-ion conductor Na<sub>3</sub>PS<sub>4</sub> are not fully understood. We present here a comprehensive analysis based on diffraction (Bragg, pair distribution function), spectroscopy (impedance, Raman, NMR, INS) and <i>ab-initio</i> simulations aimed at elucidating the synthesis-property relationships in Na<sub>3</sub>PS<sub>4</sub>. We consolidate previously reported interpretations about the local structure of ball-milled samples, underlining the sodium disorder and showing that a local tetragonal framework more accurately describes the structure than the originally proposed cubic one. Through variable-pressure impedance spectroscopy measurements, we report for the first time the activation volume for Na<sup>+</sup> migration in Na<sub>3</sub>PS<sub>4</sub>, which is ~30% higher for the ball-milled samples. Moreover, we show that the effect of ball-milling on increasing the ionic conductivity of Na<sub>3</sub>PS<sub>4</sub> to ~10<sup>-4</sup> S/cm can be reproduced by applying external pressure on a sample from conventional high temperature ceramic synthesis. We conclude that the key effects of mechanochemical synthesis on the properties of solid electrolytes can be analyzed and understood in terms of pressure, strain and activation volume.</p> </div>

The influence of composition on polymorphism, structure and charge carrier concentration in TL-2201.

1994 ◽  
Vol 235-240 ◽  
pp. 539-540
Author(s):  
C. Ström ◽  
S.-G. Eriksson ◽  
J. Albertsson ◽  
N. Winzek
Keyword(s):  
Charge Carrier ◽  
Carrier Concentration ◽  
Charge Carrier Concentration

scholarly journals Internal Factors Affecting the Surface Rumpling of a β-NiAlHf Coating

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 436
Author(s):  
Liang Liu ◽  
Jian He ◽  
Yaoge Dong ◽  
Hongbo Guo
Keyword(s):  
Physical Vapor Deposition ◽  
Elevated Temperatures ◽  
Coefficient Of Thermal Expansion ◽  
Dominant Role ◽  
Cyclic Loads ◽  
Internal Factor ◽  
Internal Factors ◽  
Factors Affecting ◽  
Mismatch Stress ◽  
Thermal Mismatch Stress

β-NiAl coatings on a superalloy substrate will inevitably result in severe rumpling at elevated temperatures; however, the associated rumpling mechanisms are not completely understood. The scale rumpling behavior of a β-NiAlHf coating deposited by electron beam physical vapor deposition (EB-PVD) on single crystal superalloy IC21 was investigated in this work. Some internal factors, including the mismatch in the coefficient of thermal expansion and the stress induced by the growth of oxide scale and the phase transformation, were taken into consideration. The thermal mismatch stress between the coating and substrate was the main internal factor responsible for rumpling behavior during thermal cyclic loads, while the phase degradation from β-NiAl to γ’-Ni3Al in the coating played a dominant role during static thermal loads.

scholarly journals Investigating the Factors Affecting the Ionic Conduction in Nanoconfined NaBH4

Inorganics ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 2
Author(s):  
Xiaoxuan Luo ◽  
Aditya Rawal ◽  
Kondo-Francois Aguey-Zinsou
Keyword(s):  
Ionic Conductivity ◽  
Ionic Conduction ◽  
Metal Hydrides ◽  
Ionic Conductivities ◽  
Effective Strategy ◽  
Li Ion Batteries ◽  
Large Cage ◽  
Factors Affecting ◽  
Li Ion ◽  
Mcm 41

Nanoconfinement is an effective strategy to tune the properties of the metal hydrides. It has been extensively employed to modify the ionic conductivity of LiBH4 as an electrolyte for Li-ion batteries. However, the approach does not seem to be applicable to other borohydrides such as NaBH4, which is found to reach a limited improvement in ionic conductivity of 10−7 S cm−1 at 115 °C upon nanoconfinement in Mobil Composition of Matter No. 41 (MCM-41) instead of 10−8 S cm−1. In comparison, introducing large cage anions in the form of Na2B12H12 naturally formed upon the nanoconfinement of NaBH4 was found to be more effective in leading to higher ionic conductivities of 10−4 S cm−1 at 110 °C.

scholarly journals When band convergence is not beneficial for thermoelectrics

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Junsoo Park ◽  
Maxwell Dylla ◽  
Yi Xia ◽  
Max Wood ◽  
G. Jeffrey Snyder ◽  
...  
Keyword(s):  
Charge Carrier ◽  
First Principles ◽  
Design Principle ◽  
Phonon Scattering ◽  
Charge Carrier Concentration ◽  
Deformation Potential ◽  
Interband Scattering ◽  
Improved Performance ◽  
Full Heusler ◽  
Electron Phonon Scattering

AbstractBand convergence is considered a clear benefit to thermoelectric performance because it increases the charge carrier concentration for a given Fermi level, which typically enhances charge conductivity while preserving the Seebeck coefficient. However, this advantage hinges on the assumption that interband scattering of carriers is weak or insignificant. With first-principles treatment of electron-phonon scattering in the CaMg2Sb2-CaZn2Sb2 Zintl system and full Heusler Sr2SbAu, we demonstrate that the benefit of band convergence can be intrinsically negated by interband scattering depending on the manner in which bands converge. In the Zintl alloy, band convergence does not improve weighted mobility or the density-of-states effective mass. We trace the underlying reason to the fact that the bands converge at a one k-point, which induces strong interband scattering of both the deformation-potential and the polar-optical kinds. The case contrasts with band convergence at distant k-points (as in the full Heusler), which better preserves the single-band scattering behavior thereby successfully leading to improved performance. Therefore, we suggest that band convergence as thermoelectric design principle is best suited to cases in which it occurs at distant k-points.

scholarly journals Performance-tuning of PVA-based gel electrolytes by acid/PVA ratio and PVA molecular weight

2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Saeideh Alipoori ◽  
M. M. Torkzadeh ◽  
Saeedeh Mazinani ◽  
Seyed Hamed Aboutalebi ◽  
Farhad Sharif
Keyword(s):  
Molecular Weight ◽  
Ionic Conductivity ◽  
Charge Carrier Concentration ◽  
Fine Tuning ◽  
Performance Tuning ◽  
Practical Applications ◽  
High Performing ◽  
Flexible Devices ◽  
Gel Electrolytes ◽  
Ion Conducting

AbstractThe significant breakthroughs of flexible gel electrolytes have attracted extensive attention in modern wearable electronic gadgets. The lack of all-around high-performing gels limits the advantages of such devices for practical applications. To this end, developing a multi-functional gel architecture with superior ionic conductivity while enjoying good mechanical flexibility is a bottleneck to overcome. Herein, an architecturally engineered gel, based on PVA and H3PO4 with different molecular weights of PVA for various PVA/H3PO4 ratios, was developed. The results show the dependence of ionic conductivity on molecular weight and also charge carrier concentration. Consequently, fine-tuning of PVA-based gels through a simple yet systematic and well-regulated strategy to achieve highly ion-conducting gels, with the highest ionic conductivity of 14.75 ± 1.39 mS cm-1 have been made to fulfill the requirement of flexible devices. More importantly, gel electrolytes possess good mechanical robustness while exhibiting high-elasticity (%766.66 ± 59.73), making it an appropriate candidate for flexible devices.

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.

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