Formation Behavior and High Electrical Conductivity of Metastable Lithium Iron Silicate Crystals in Rapid Quenching of Li2O–Fe2O3–SiO2 Melts. Issue 3 (14th December 2013)

• Record Type: Journal Article
• Authors: Togashi, Takuya; Honma, Tsuyoshi; Komatsu, Takayuki; Ferreira, J.
• Is Part Of: Journal of the American Ceramic Society. Volume 97:Issue 3(2014)
• Page Start: 835
• Page End: 842
• Publication Date: 2013-12-14
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.12701
• Languages: English
• ISSNs: 0002-7820

Abstract

<abstract abstract-type="main" id="jace12701-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The formation behavior of spinel‐type LiFeSiO₄ crystals in the quenching of melts in the Li₂O–Fe₂O₃–SiO₂ system was examined. It was found that high quenching rates of 10³ ~ 10⁶ K/min are favorable for the formation of LiFeSiO₄ crystals. The rapid quenched samples showed high electrical conductivities of the order of 10⁻²–10⁻⁴ S/cm at room temperature and low activation energy for conduction of 0.1–0.2 eV. Both valences of Fe²⁺ and Fe³⁺ were present in the melt‐quenched samples, and rapid‐quenched samples showed ferrimagnetism. It is proposed that the chemical composition of LiFeSiO₄ formed in the rapid quenching of melts would be spinel‐type Li_{1 + <italic>x</italic>}Fe³⁺_{1 − <italic>x</italic>}Fe²⁺_{<italic>x</italic>}SiO₄. Because the Li_{1 + <italic>x</italic>}Fe³⁺_{1 − <italic>x</italic>}Fe²⁺_{<italic>x</italic>}SiO₄ crystalline phases are metastable, the rapid quenching technique is necessary for their synthesis. The effects of quenching rate and composition on the formation of spinel‐type LiFeSiO₄ and on the electrical conductivity of quenched samples were discussed.</p> </abstract>