A method for directly synthesizing high-purity, high-density chalcopyrite blocks by solid-state reaction

Abstract

The invention discloses a method for directly synthesizing high-purity and high-density chalcopyrite blocks by solid-phase reaction. Analytical pure copper sulfide and analytical pure ferrous sulfide are weighed according to the molar ratio of 1:1, ground and mixed evenly as Starting material; the mixture powder is pressed into a cylinder, and the end face is covered with a sulfur powder disc, and the platinum-graphite double sample chamber is sealed in the order of sulfur powder disc-mixture cylinder-sulfur powder disc to form a sample, and placed in In the h-BN tube, h-BN is used as the pressure transmission medium; the high-temperature and high-pressure reaction is carried out in a six-sided top press, and the cylindrical sample after the reaction is taken out, polished, ultrasonically cleaned and air-dried, and then stored in an inert gas atmosphere. The density of the obtained chalcopyrite block is close to the theoretical density, presents a standard cylindrical shape, and can be directly used for the test of electrical conductivity and thermal conductivity. In addition, one or both of tin sulfide or cobalt sulfide are added to the raw material, Chalcopyrite derivatives doped with tin and cobalt can be formed, and the electromagnetic properties of chalcopyrite can be optimized.

Description

technical field [0001] The invention relates to a method for directly synthesizing high-purity and high-density chalcopyrite blocks by solid phase reaction, which belongs to the field of material science research. Background technique [0002] Chalcopyrite is a copper-iron sulfide found all over the world. It is a typical mineral of hydrothermal origin and an important copper resource. Natural chalcopyrite mostly presents irregular granular and dense massive aggregates, and crystals are extremely rare. Its crystal structure is a tetragonal crystal system, which is a sphalerite-like structure. Cu and Fe are respectively located at the corners of the tetrahedron. Cu and Fe are linked by S. The chemical formula is CuFeS 2 . Chalcopyrite has good electrical conductivity and is a semiconductor. The study of its electrochemical properties is of great significance for explaining the origin of hydrothermal fluids, electrolytic destruction, and wet copper smelting. More importantl...

AI Technical Summary

Problems solved by technology

However, for the quantitative study of thermoelectric materials in the field of materials science, the disadvantage of natural beneficiation is that the purity of natural chalcopyrite cannot be guaranteed and the composition cannot be controlled. The reasons are: (1) The symbiotic minerals of natural chalcopyrite include pyrite and pyrrhotite ore, bornite, chalcocite, chalcocite, etc., although the beneficiation method can select relatively pure chalcopyrite particles from the paragenetic mineral aggregates, most of the inclusions of the paragenetic minerals are at the micron level, and the inclusions The substances in the body are different, and it is difficult to identify them through mineral phase mirror ore dressing

(2) Natural chalcopyrite is affected by the formation environment, often accompanied by trace substitution of various elements, such as Ag, Au, Se, Te, Sn, Ni, Co, etc., which makes the chemical composition uncontrollable

Therefore, although the vacuum tube can avoid the oxidation of sulfide, since the open system cannot solve the problems of desulfurization reaction and sulfur volatilization, it is actually difficult to carry out solid-phase reaction according to the ideal ratio of chalcopyrite, and the purity of the product cannot be guaranteed.