ac conductivity and transport studies in phosphate glasses with NASICON-type chemistry

doi:10.1016/0167-2738(95)00175-6

Solid State Ionics

Volume 81, Issues 1–2, October 1995, Pages 145-156

https://doi.org/10.1016/0167-2738(95)00175-6 Get rights and content

Abstract

ac conductivity studies conducted on glasses with NASICON-type chemistry reveal many universalities in their behaviour. It is found that the total conductivity of all the glasses at all temperatures can be fitted well with a double power law using s₁ = 0.5 and s₂ = 1.0. It is found that the plots of reduced conductivity (with respect to the dc conductivity) versus reduced frequency (with respect to M″ peak frequency) are superimposable for all the glasses at all temperatures, indicating that the ionic conductivity in these materials is independent of a number of factors like the nature and concentration of the cation and structure of the glass.

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While optimizing the crystalline phase of the glass-ceramic electrolytes has been effective in enhancing the ionic conductivity, it is important to note that glass electrolytes actually possess much lower ionic conductivity compared to their crystalline counterparts, and thus it is quite counterintuitive that ionic conductivity of hybrid glass-ceramic electrolytes is higher than pure ceramic phases [15,16]. For example, the ionic conductivity of Li1.3Al0.3Ti1.7(PO4)3 glass-ceramic is about 1 × 10−4 S cm−1, much higher than 6 × 10−5 S cm−1 of Li1.3Al0.3Ti1.7(PO4)3 ceramic [17,18], while the corresponding conductivity of glass phase is orders of magnitude smaller, in the range of 10−10–10−8 S cm−1 [19–21]. This begs for an explanation, and the reason may lie in grain boundaries of ceramics, which exhibit high resistance to the ionic conduction [22].
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ac conductivity and transport studies in phosphate glasses with NASICON-type chemistry

Abstract

J. Non-Cryst. Solids

J. Non-Cryst. Solids

J. Non-Cryst. Solids

Solid State Ionics

Solid State Ionics

Solid State Ionics

Solid State Commun.

Solid State Ionics

J. Non-Cryst. Solids

Prog. Solid State Chem.

Mater. Res. Bull.

Mater. Res. Bull.

J. Solid State Chem.

Solid State Ionics

Phys. Rev. B

Phys. Rev. B

Nature