UA120661U - METHOD OF GROWING SOLID SOLUTIONS OF THE COMPOSITION (Cu1-XAgX) 7GeS5I BY THE METHOD OF DIRECTED CRYSTALIZATION FROM MELT-SOLUTION - Google Patents

Abstract

A method of growing solid solutions of (Cu1-xAgx) 7GeS5I composition by direct melt-crystallization method involves the step heating of vacuum quartz ampoules, from pre-synthesized tetrahalogen halides of Cu7GeS5I and Ag7GeS5I, The heating is carried out to a maximum temperature which is 50 K above the melting point, and the charge is maintained at this temperature for 72 hours. The further growth of single crystals at a rate of 0.4-0.5 mm / h. in special vacuum-filled quartz containers.

Description

A useful model belongs to the field of inorganic chemistry and inorganic materials science, in particular to methods of growing single crystals of tetrahalogen sulfides, some of which are promising superionic materials with high cationic conductivity in the solid state.

The closest to the proposed method is the method of growing single crystals of argentum(I) pentathiogermanate(U) iodide Aa7se55i by the method of directed crystallization from the melt (11.

The task of a useful model is to obtain a new superionic material with high cationic conductivity in the solid state.

The task is solved in the method of growing solid solutions of the composition (SyxAakh)7c1e55iI by the method of directional crystallization from a melt - a solution that includes stepwise heating of vacuumed quartz ampoules from pre-synthesized tetrarhalochalcogenides Si7Sbeb»iI and Ad7Zeby taken in stoichiometric ratios, according to a useful model, heating is carried out to the maximum temperature, which is 50 K higher than the melting temperature, and the charge is kept at this temperature for 72 hours, and further growth of single crystals is carried out at a rate of 0.4-0.5 mm/h. in vacuumed quartz containers of a special shape.

The method is implemented as follows.

The synthesis of solid solutions of the composition (Сy:-хАдх)/sezvi to obtain single crystals was carried out from previously synthesized tetrarhalogenides Си7сеюби and Ад7зеби taken in stoichiometric ratios in vacuumed quartz ampoules.

The synthesis mode included step heating at a rate of 100 K/h. to 973 K with exposure at this temperature for 24 hours, further increasing the temperature at a rate of 50

K/hour to a value 50 K higher than the melting temperature and holding at this temperature for 72 hours. Cooling was carried out with the furnace turned off.

The growth of Si?7beb»iI single crystals by crystallization from a melt solution was carried out in a two-zone tubular resistance furnace using a quartz container of a special configuration. The technological conditions for growing single crystals are given in the table (Table).

Table

З In order to homogenize the melt, the ampoule was kept in the melt zone for 24 hours.

Single crystal growth consists of seed formation in the lower cone-shaped part of the container by collective recrystallization for 48 hours and crystal growth on the formed seed. The optimal speed of movement of the crystallization front was 0.4-0.5 mm/hour, the cooling rate to room temperature was 5 K/hour. According to this method, single crystals of solid solutions of the composition (Си:-хАдх)/levvi (х-0.25, 0.5, 0.75) of dark gray color with a metallic luster of 30-40 mm in length and 10-15 mm in diameter were obtained (Fig. 1).

The powders of the obtained single crystals |2| were studied using the X-ray phase analysis method and it was established that compounds and solid solutions based on them crystallize in cubic syngonia, space group. E-43t, 2-4. With the help of the BISMOI 04 |Z, 4) program, the corresponding values of the lattice parameters were calculated. The concentration dependence (Fig. 2) of the lattice period is described by Vegard's rule and has a monotonic character with a negative deviation from the linear one, which is associated with the disorder (distortion) of the anionic sublattice due to the difference in the crystal chemical radii of Ad" and C" and the change in the ratio of the occupancy of equivalent positions during cationic substitution.

A useful model can be used in the preparation of a patent-protected superionic material with high cationic conductivity at room temperature.

Sources of information: 1. Pat. 114854 Ukraine IPC SZOV 13/04, SZOV 13/00, SZOV 9/00. Cultivation method

Ad7Seb5iI by the method of directed crystallization from melt - solution / A.I. Pogodin, O.P. Kokhan,

Solomon A.M., Izai V.Yu., Studeniak I.P.; applicant and owner of the patent "UzhNU" DVNZ. - MO 114854; statement 05.09.16.; published 27.03.17., Bul. Mo 6. - Prototype

2. Kovba L.M.

Radiography in inorganic chemistry / L.M. Kovba. - M.: Moscow State University Publishing House, 1991. - 256 p. 3. I otsbg 0. Ipaehipud m/yyp She zissevzvzime dispoiotu teiipoa, BISMOI 04. // Maiegiaie Bigisishge. 2004, 11(2), 79. 4. Yu.

Rougdeg racet ipaehipd apa (Ve dispoioptu aidogyit. // 7. KgiziaNyodg. 5yrri. 2007,

Claims (1)

26, 191-196. USEFUL MODEL FORMULA The method of growing solid solutions of the composition (Si1-xAdh)/ylezZviI by the method of directed crystallization from the melt-solution, which includes stepwise heating of vacuumed quartz ampoules, from pre-synthesized tetrarhalochalcogenides Si7Syeb»5iI and Ad;SZebby, taken in stoichiometric ratios, which differs in that the heating is carried out to the maximum temperature, which is 50 K higher than the melting temperature, and the charge is kept at this temperature for 72 hours. and carry out further growth of single crystals at a speed of 0.4-0.5 mm/h. in vacuumed quartz containers of a special shape. OKKO OK VKKKVO KK EK OO s sh t -sh- o OO sht- s ZO KK M V s ХК хх жх AEN (Spo Ado noya ISpezbdol novy Eva vAdyzvOeia Fig 1 1MYU | teh B, 4 What sn NEK nt - ! p nn g g - o 4; 5 KO A p ei y M, as z mol le AVK ayu Fig 7