Processing and Properties of Amorphous Manganese Dioxide Formed by Sol-Gel Procedures

1998 ◽  
Vol 548 ◽  
Author(s):  
Jun John Xu ◽  
Stefano Passerini ◽  
Boone B. Owens ◽  
William H. Smyrl
Keyword(s):  
Water Content ◽  
Manganese Dioxide ◽  
Exchange Process ◽  
Sol Gel ◽  
Cycling Performance ◽  
Lithium Intercalation ◽  
Solvent Exchange ◽  
Preliminary Results ◽  
Composition And Structure ◽  
Different Temperatures

ABSTRACTSol-gel derived amorphous manganese dioxide (a-MnO2) showed extremely high reversible lithium intercalation capacity. The composition and structure of the material were modified by heating at different temperatures. Cycling performance of the modified samples suggests that lowering the water content in the material is beneficial, while introducing crystallinity is detrimental, to its cyclability. A novel double-solvent-exchange process was tried for the processing of the material. Preliminary results indicated significant improvement in the reversibility of the insertion/release cycles.

Sol-gel-derived glass scaffold with high pore interconnectivity and enhanced bioactivity

2009 ◽  
Vol 24 (12) ◽  
pp. 3495-3502 ◽  
Author(s):  
Ana C. Marques ◽  
Rui M. Almeida ◽  
Amath Thiema ◽  
Shaojie Wang ◽  
Matthias Falk ◽  
...  
Keyword(s):  
Exchange Process ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
Three Dimensional ◽  
Average Diameter ◽  
Solvent Exchange ◽  
Sol Gel Transition ◽  
The One

We report on the preparation of a bioactive CaO–SiO2 monolithic scaffold with interconnected bimodal nanomacro porosity, which simulates the morphology of a natural trabecular bone, by a newly developed modified sol-gel process. This method inherently creates nanopores, whose average diameter can be tailored to approximately 5–20 nm by solvent exchange. To achieve interconnected macroporosity (pores ∼5–300 μm in size), a polymer [poly(ethylene oxide)] is added, which causes phase separation simultaneously with the sol-gel transition. High-resolution scanning electron microscopy and mercury intrusion porosimetry demonstrate a high degree of three-dimensional interconnectivity and sharp distributions of pore size. In vitro bioactivity tests in simulated body fluid (SBF) show bioactivity of the material after soaking for approximately 5 h, as verified by the formation of a hydroxyapatite layer deep into the scaffold structure. Analysis of the SBF after the reaction indicates the dissolution of the samples, another desired feature of temporary scaffolds for bone regeneration. MG63 osteoblast-like cells seeded on our sol-gel glass samples responded better to samples with nanopores enlarged by a solvent exchange process than to the one with normal nanopores. Thus, the benefits of the high surface area achieved by sol-gel and solvent exchange procedures are most clearly demonstrated for the first time.

Development of High Permeability Core Materials for Embeddable Inductors in Flexible Organic Substrates

2003 ◽  
Vol 769 ◽  
Author(s):  
C. K. Liu ◽  
P. L. Cheng ◽  
S. Y. Y. Leung ◽  
T. W. Law ◽  
D. C. C. Lam
Keyword(s):  
Low Temperature ◽  
Sol Gel ◽  
Circuit Board ◽  
Organic Substrates ◽  
Circuit Boards ◽  
High Permeability ◽  
Electrical Measurements ◽  
Different Temperatures ◽  
Spiral Inductors ◽  
Ceramic Tape

AbstractCapacitors, resistors and inductors are surface mounted components on circuit boards, which occupy up to 70% of the circuit board area. For selected applications, these passives are packaged inside green ceramic tape substrates and sintered at temperatures over 700°C in a co-fired process. These high temperature processes are incompatible with organic substrates, and low temperature processes are needed if passives are to be embedded into organic substrates. A new high permeability dual-phase Nickel Zinc Ferrite (DP NZF) core fabricated using a low temperature sol-gel route was developed for use in embedded inductors in organic substrates. Crystalline NZF powder was added to the sol-gel precursor of NZF. The solution was deposited onto the substrates as thin films and heat-treated at different temperatures. The changes in the microstructures were characterized using XRD and SEM. Results showed that addition of NZF powder induced low temperature transformation of the sol-gel NZF phase to high permeability phase at 250°C, which is approximately 350°C lower than transformation temperature for pure NZF sol gel films. Electrical measurements of DP NZF cored two-layered spiral inductors indicated that the inductance increased by three times compared to inductors without the DP NZF cores. From microstructural observations, the increase is correlated with the changes in microstructural connectivity of the powder phase.

scholarly journals Solvent-exchange process in MOF ultrathin films and its effect on CO2 and methanol adsorption

2021 ◽  
Vol 590 ◽  
pp. 72-81
Author(s):  
M.A. Andrés ◽  
P. Fontaine ◽  
M. Goldmann ◽  
C. Serre ◽  
O. Roubeau ◽  
...  
Keyword(s):  
Ultrathin Films ◽  
Exchange Process ◽  
Solvent Exchange ◽  
Methanol Adsorption

Reversal of triboelectric charges on sol–gel oxide films annealed at different temperatures

2021 ◽  
Vol 118 (24) ◽  
pp. 243902
Author(s):  
Yongqiao Zhu ◽  
Shiquan Lin ◽  
Wenchao Gao ◽  
Miao Zhang ◽  
Dawei Li ◽  
...  
Keyword(s):  
Sol Gel ◽  
Oxide Films ◽  
Different Temperatures

Magnetic Resonance Imaging Spatial and Time Study of Lung Water Content in Newborn Lamb: Methods and Preliminary Results

2008 ◽  
Vol 43 (6) ◽  
pp. 470-480 ◽  
Author(s):  
Romain Viard ◽  
Pierre Tourneux ◽  
Laurent Storme ◽  
Julie-Marie Girard ◽  
Nacim Betrouni ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Water Content ◽  
Time Study ◽  
Resonance Imaging ◽  
Lung Water ◽  
Newborn Lamb ◽  
Preliminary Results ◽  
Lung Water Content

ChemInform Abstract: Sol-Gel Synthesis of Carbon/Silica Gel Electrodes for Lithium Intercalation.

ChemInform ◽  
2010 ◽  
Vol 31 (8) ◽  
pp. no-no
Author(s):  
Gerko Oskam ◽  
Peter C. Searson ◽  
T. Richard Jow
Keyword(s):  
Silica Gel ◽  
Sol Gel ◽  
Lithium Intercalation ◽  
Sol Gel Synthesis

scholarly journals Effect of surface carbonates on the cyclability of LiNbO3-coated NCM622 in all-solid-state batteries with lithium thiophosphate electrolytes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
A-Young Kim ◽  
Florian Strauss ◽  
Timo Bartsch ◽  
Jun Hao Teo ◽  
Jürgen Janek ◽  
...  
Keyword(s):  
Solid State ◽  
Solid Electrolyte ◽  
Sol Gel ◽  
Rate Capability ◽  
Cycling Performance ◽  
Side Reactions ◽  
Bulk Solid ◽  
Solid State Batteries ◽  
The Individual ◽  
Surface Carbonates

AbstractWhile still premature as an energy storage technology, bulk solid-state batteries are attracting much attention in the academic and industrial communities lately. In particular, layered lithium metal oxides and lithium thiophosphates hold promise as cathode materials and superionic solid electrolytes, respectively. However, interfacial side reactions between the individual components during battery operation usually result in accelerated performance degradation. Hence, effective surface coatings are required to mitigate or ideally prevent detrimental reactions from occurring and having an impact on the cyclability. In the present work, we examine how surface carbonates incorporated into the sol–gel-derived LiNbO3 protective coating on NCM622 [Li1+x(Ni0.6Co0.2Mn0.2)1–xO2] cathode material affect the efficiency and rate capability of pellet-stack solid-state battery cells with β-Li3PS4 or argyrodite Li6PS5Cl solid electrolyte and a Li4Ti5O12 anode. Our research data indicate that a hybrid coating may in fact be beneficial to the kinetics and the cycling performance strongly depends on the solid electrolyte used.

Processing and Performance of V205 Xerogel, Aerogel, and Aerogellike Materials as Lithium Intercalation Hosts

1998 ◽  
Vol 548 ◽  
Author(s):  
Leland H. Manhart ◽  
Jun John Xu ◽  
Fabrice Coustier ◽  
Stefano Passerini ◽  
Boone B. Owens ◽  
...  
Keyword(s):  
Lithium Batteries ◽  
Methyl Formate ◽  
Sol Gel ◽  
Specific Capacity ◽  
Lithium Intercalation ◽  
Composite Electrodes ◽  
Rechargeable Lithium Batteries ◽  
Exchange Processes ◽  
And Performance ◽  
Sol Gel Synthesis

ABSTRACTVarious forms of vanadium pentoxide, including xerogel, aerogel, and aerogel-like forms, were prepared by sol-gel synthesis and processed by novel procedures following synthesis. It was demonstrated that the intrinsic thermodynamics of lithium intercalation of the ARG and ARG-like materials prepared by solvent exchange processes involving methyl formate (MF/ARG and MF/ARG-xslike) are identical, while they are drastically different from those of the parent XRG, which gives rise to significantly increased specific energies for the MF/ARG or MF/ARG-like as lithium intercalation hosts. All three forms are capable of reversibly intercalating up to four moles of Li+ ions per mole of V205 electrochemically and can be cathode candidates for rechargeable lithium batteries. Various processing methods for fabricating composite electrodes with the XRG led to specific capacity in the range of 300 to 350 mAh/g at C4Li/ 20 rate, and good cyclability.

scholarly journals A novel ceramic material with medical application

2008 ◽  
Vol 2 (1) ◽  
pp. 19-22 ◽  
Author(s):  
Joanna Podporska ◽  
Marta Błażewicz ◽  
Barbara Trybalska ◽  
Łukasz Zych
Keyword(s):  
Body Fluid ◽  
Crystallization Process ◽  
Sol Gel ◽  
Medical Application ◽  
In Vitro Test ◽  
Glass Crystallization ◽  
Complex Shapes ◽  
Different Temperatures ◽  
Vitro Test

Until now the basic methods used in manufacturing of wollastonite have been chemical (melting together with glass crystallization process, chemical coprecipitation) and sol - gel methods. A new and promising way of wollastonite fabrication is controlled pyrolysis of polysiloxane precursors with inorganic fillers. Heat treatment of such mixtures leads to the formation of wollastonite-containing ceramics already at about 1000?C. This is a relatively inexpensive and efficient method which enables to obtain complex shapes of the samples. The aim of this work was to obtain sintered, wollastonite-containing bioceramics and determine its bioactive features. Samples were sintered at three different temperatures: 1000, 1100 and 1200?C. Then the bioactivity of the wollastonite-containing ceramics was investigated by the ?in vitro? test in simulated body fluid. On the basis of the achieved results, it can be assumed that the obtained material possesses bioactive features.

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