JPS6285B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel Zn-Ti-S compound and a method for producing the same. Conventionally, Zn-Ti-S compounds have not been known, and the object of the present invention is to develop a novel compound useful as a Zn-Ti-S electrode material with the general formula (Zn _X Ti _1-X ) _Y S ₃₂ (However, X and Y are the same as above)
The present invention provides a compound represented by: and a method for producing the same. The stable compositional region of the compound of the present invention can be represented by the general formula: (Zn _X Ti _1-X ) _Y S ₃₂ (however,
X, Y represent the same values as above), and a=
It has a 9.84 Å face-centered cubic lattice crystal structure.
In the unit cell of a compound with a typical composition,
Examples include Zn ₂ Ti ₁₈ S ₃₂ . This representative compound is S
It has a crystal structure based on cubic close packing, with 16
Ti is statistically present in 16 octahedral gaps, 2 Ti in the other 16 octahedral gaps, and 2 Zn in 8 tetrahedral gaps. The distribution of statistically existing metal ions is accompanied by short-range order. The interplanar spacing d (Å) of this compound (d _pbs is the observed value, d _calc is the calculated value), the interplanar index hkl, and the relative diffraction intensity I/I ₁ (%) of powder X-ray diffraction are shown in Table 1 below. That's right.

【table】

[Table] * Broad diffraction line This compound is Pauli paramagnetic, electrically metallic, and has a statistical distribution of metal ions, making it useful as an electrode material. The method for producing these compounds is as follows: (1) Titanium or titanium sulfide or a mixture thereof and zinc or zinc sulfide or a mixture thereof are mixed so that the atomic ratio of zinc to titanium is 0.087 to 0.087.
0.124 and the atomic ratio of sulfur to the sum of titanium and zinc is 1.55 to 1.65, and the mixture is heated to 1100°C or higher under vacuum. can be mentioned. In the production method (1) above, if the atomic ratio of zinc to titanium is less than 0.087, titanium sulfide will be mixed as an impurity. Moreover, if the ratio exceeds 0.124, zinc sulfide will be mixed as an impurity, and a Zn ₂ Ti ₁₈ S ₃₂ phase as a single phase cannot be obtained in any case. Furthermore, if the atomic ratio of sulfur to the sum of titanium and zinc is less than 1.55, zinc sulfide and titanium sulfide (Ti ₂ S ₃ −4H) will coexist. Also, the ratio
When it exceeds 1.65, titanium sulfide (TiS ₂ −2H) is mixed, and both Zn ₂ Ti ₁₈ S ₃₂ as a single phase.
I can't get the phase. Heating must be performed at a temperature of 1100°C or higher under vacuum. If the heating temperature is lower than 1100°C, the reaction rate will be slow and implementation will be difficult. Example 1 Ti and S were vacuum sealed in a quartz glass tube and heated at 900°C to synthesize _{TiS 1.70} . This composition was determined from the weight change when it was converted to TiO ₂ by heating in air. Next, TiS _1.70 , _ZnS , and Ti are
The mixture was mixed at a ratio of Zn ₂ Ti ₁₈ S ₃₂ , vacuum sealed in a quartz glass tube, heated at 1200° C. for 5 hours, and then quenched in water. It was confirmed by powder X-ray diffraction, transmission electron beam diffraction, and optical microscope observation that titanium sulfide and zinc sulfide were not mixed in the obtained compound. The diffraction pattern could be indexed according to the cubic system with a=9.843 Å shown in Table 1 above.

Claims (1)

[Scope _of Claims] _1. A compound represented by _the general formula ( _Zn 2. Titanium, titanium sulfide, or a mixture thereof and zinc, zinc sulfide, or a mixture thereof, with an atomic ratio of zinc to titanium of 0.087 to 0.124.
So, the atomic ratio of sulfur to the sum of titanium and zinc is
Mix in a ratio of 1.55 to 1.65 and the mixture under vacuum.
_{General formula ( Zn}
19.4 to 20.6).