JPH0649592B2 - Superion conductive glass using Cu + ions - Google Patents

Description

TECHNICAL FIELD The present invention relates to an ion conductive glass applied to, for example, an all-solid-state battery, and more particularly to a novel highly conductive ion conductive glass using copper ions. .

2. Description of the Related Art As a charge carrier, an electrolyte solution in which ions contribute to conduction instead of electrons and holes has been known for a long time, and has been applied to batteries and the like. A conductive solid has been synthesized.

Electrolyte solution has high ionic conductivity, but since it is a liquid, it has a problem of leaking to the outside of electronic parts that use it, which causes performance deterioration of parts and damage to peripheral parts. There was a drawback. Solid electrolytes have been developed as a solution to this drawback.

As a solid electrolyte, a zirconia solid solution discovered by Nernst in the old days is known. Furthermore, 197
Since it was discovered by Kunze in 3 years that AgI-Ag ₂ SeO ₄ type glass has high ionic conductivity, many glassy solid ionic conductivities have been synthesized. These are called "superion conducting glasses" to distinguish them from crystals. Compared with crystals, superionic conductive glass has the unique characteristics of glass, such as being easy to obtain a homogeneous and isotropic material without grain boundaries, being excellent in formability, and being easy to be thinned. and which further present inventors have _{AgI-Ag 2 O-P 2} O
_As reported for ₅ series glass [J. Electr
ochem.Soc.vol.124, P.1659 (1977)], vitrification is also advantageous in improving ionic conductivity as compared with crystals.

As the super-ionic conductive glass, silver ions have been most studied, and in addition to the above-mentioned papers, there are many, including those of the present inventor, and JP-A-55-104006 and the like are known. Recently, interest in lithium ions and sodium ions has also increased (for example, JP-A-55).
-7593 and JP-A-59-107942).

Problems to be Solved by the Invention However, it cannot be said that these conventional super ionic conductive glasses have sufficiently high ionic conductivity, and their use conditions are limited. In addition, there are many Ag ⁺ ion-conducting glasses that show a value of ionic conductivity as high as 10 ^-2 S · cm ^-1 , and currently they are the mainstream of super-ion-conducting glasses, but they are generally expensive and therefore expensive. There is a problem that it is not suitable for electronic parts.

In view of the above problems, the present invention provides a new copper ion conductive glass which has higher conductivity than silver ion conductive glass, is low in cost, and has high output.

Means for Solving the Problems In order to solve the above problems, the present invention is based on the following three-element phase diagram of CuI—Cu ₂ O—MoO _{3 in which} the components of glass are points A, B and C shown in the table below. , D, E and F are superionic conductive glasses using Cu ⁺ ions in the composition region.

It is possible to use Cu ⁺ ions belonging to the same group in the periodic table instead of the working Ag ⁺ ions, but there is a problem that Cu ⁺ ions are easily oxidized to divalent Cu ⁺⁺ ions. Yes, little researched yet. U.S. Pat. No. 4,226,628 discloses P ₂ O ₅ based Cu ₂
A ternary glass containing O and copper halide is disclosed, which focuses on the electrochromic phenomenon, and the ionic conductivity shown here is two orders of magnitude lower than that of silver ion. . Also, Ange of Purdue University
ll et al., while quoting the above-mentioned U.S. Patent, reported on Cu ⁺ ion conductive glass [Solid State Ionic
s, vol.13, p. 105-109 (1984)], which are those described for the glass forming region of the _{CuI-Cu 2 O-P 2} O 5 ternary system, the present invention, CuI-Cu ₂ O
-There is no previous report on MoO ₃ ternary system.

The present inventors have, compared CuI-Cu ₂ O, results of wide experimentation for various compounds, the use of MoO _3, in specific areas of the ternary system, not observed in a conventional super-ionic conductor glass It was found that Cu ⁺ ion conductive glass with high ionic conductivity can be obtained.

Examples Hereinafter, examples of the present invention will be described with reference to the drawings.

Commercially available CuI, Cu ₂ O and MoO ₃ powders (all having a purity of 99% or more) are used as starting materials used in the production of each of the examples. The samples are weighed so as to have the composition of each sample number shown in Table 1, and these powders are sufficiently mixed in an agate mortar. Put this mixed powder in a quartz glass ampoule,
Enclose in vacuum. This is vacuum-melted at 450 to 700 ° C. for about 1 hour depending on the composition. This molten material together with the quartz ampoule is taken out from the electric furnace into the air and cooled and solidified. Depending on the case, you may cool by putting a quartz ampoule in ice water.

The ionic conductivity σ and the glass transition temperature Tg of each of the samples thus obtained were measured. The ionic conductivity σ was measured by a conventional method using a vector impedance meter or a dielectric loss measuring instrument. The glass transition temperature Tg was determined by differential thermal analysis and thermal expansion curve. Table 1 shows the measurement results of each sample. The ionic conductivity σ indicates a value at room temperature of 25 ° C.

FIG. 1 shows a region where glass is formed in the CuI—Cu ₂ O—MoO ₃ ternary system of the present invention. As a result of the experiment, the desired glass is not formed outside the shaded area in FIG. For example, when a composition of CuI 20 mol%, Cu ₂ O 60 mol% and MoO ₃ 20 mol% (point G) was vacuum melted, the obtained sample became crystalline and glass was not obtained.

As a comparative example a conventional Ag ion conductive glass, the AgI-Ag ₂ O-MoO ₃ system corresponding to the composition of the Cu ⁺ ion conductive glass of the present invention, to prepare a sample in the same manner as in the above embodiment, in the same way Then, the ionic conductivity σ and the glass transition temperature Tg were measured. Table 2 shows the composition of each of these samples and the measurement results.
The ionic conductivity σ indicates a value at room temperature of 25 ° C.

In the case of AgI-Ag ₂ O-MoO ₃ systems, not necessarily require vacuum melting, be melted in the atmosphere, that almost the same characteristic values obtained are confirmed.

Table 1 of Cu ⁺ ion conductive glass according to the composition of the present invention;
Comparing with Table 2 of Ag ⁺ ion conductive glass of the conventional example, C
Comparing the samples with the same uI and AgI contents, it can be seen that the ionic conductivity of the former is much higher than that of the latter. This can be shown more clearly in FIG.

FIG. 2 is a graph showing the composition dependence of the ionic conductivities of both, and for the same mol% CuI or AgI content, the ionic conductivity of the glass of the composition of the present invention is one digit lower than that of the conventional glass. You can see that it is higher than the above. The second
In the figure, among the glass compositions in Table 1 and Table 2, Cu
Molar ratio of ₂ O and molar ratio or Ag ₂ O and MoO ₃ of MoO ₃ is shown only the results of the first sample. Therefore, the notation of chemical composition is expressed as a pseudo binary system such as CuI—Cu ₂ MoO ₄ system or AgI—Ag ₂ MoO ₄ system.

As described above, according to the present invention, in the CuI—Cu ₂ O—MoO ₃ system ternary system, by taking the composition in the region shown in FIG. 1, the composition is much higher than the conventional one. A new Cu ⁺ ion-conducting glass with ionic conductivity can be obtained.

Further, the glass transition temperature of the samples in Table 2 is 54 to 86 ° C.
On the other hand, in the glass of the present invention, as shown in Table 1, all are 110 ° C. or higher, and the glass of the present invention can be used for special applications such as high temperature around 100 ° C. . In addition, since the mass of copper ions is much smaller than that of silver ions, the energy that can be taken out per unit mass is large, so that the feature of higher output can be expected. Further, the price of copper, which is a raw material of the ion conductive glass of the present invention, is much lower than that of silver, which is a conventional raw material of the ion conductive glass, and can be expected to be widely applied to general electronic parts.

As described above, the Cu ⁺ ion conductive glass according to the present invention is
It has excellent features such as high ionic conductivity, high temperature resistance, high output and low price.
It can be effectively used as an ion conductive material for various electronic components.

[Brief description of drawings]

FIG. 1 shows CuI showing the composition of the Cu ⁺ ion conductive glass of the present invention.
-Cu ₂ O-MoO ₃ ternary system diagram, FIG. 2 is a characteristic diagram showing the composition dependency of the ionic conductivity at room temperature of the present invention and the conventional ion-conducting glass.

Claims (1)

[Claims] 1. A glass component contains Cu ⁺ ions in a composition region surrounded by points A, B, C, D, E and F shown in the following table in the CuI-Cu ₂ O-MoO ₃ ternary phase diagram. Superion conductive glass used.