Method for preparing pyroelectric material Ag complex (Ca***La*)*Co*O

Abstract

The invention discloses a preparation method of thermoelectric material Ag compound (Ca(1-X)LaX)3Co4O9, and relates to the preparation method of Ag compound oxide thermoelectric material. The invention resolves the problems that the distribution of Ag phases in an Ag compound Ca-Co-O-based oxide is not even, the size of Ag phase particles is large, thereby leading that current carrier transporting loop is formed between Ca-Co-O-based oxide crystal grains, and leading Seebeck coefficient of the Ag compound Ca-Co-O-based oxide to be reduced evidently, and the existence of lanthanon results in decreasing the electrical conductivity of the Ca-Co-O-based oxide. The preparation methods comprises that firstly, calcium nitrate, cobalt nitrate and lanthanum nitrate are dissolved in distilled water; secondly, citric acid is add; thirdly, silver nitrate is added; fourthly, organic monomers and network agent are added; fifthly, initiating agent is added; sixthly, microwave dry is performed; seventhly, calcination is operated; eighthly, the spark plasma sintering is performed. The distribution of Ag phases in Ag compound (Ca(1-X)LaX)3Co 4O9 prepared by the methods of the invention is even, the size of the Ag phase particles is smaller than 500 nm, and the current carrier transporting loop is not formed. The Seebeck coefficient of the Ag compound (Ca(1-X)LaX)3Co4O9improves 1.7 percent to 4.9 percent than that of the Ca3Co4O9, the electrical conductivity improves 13.3 percent to 38.9 percent, and the power factor improves 21.6 percent to 35.1 percent.

Description

technical field [0001] The invention relates to a preparation method of an Ag composite oxide thermoelectric material. Background technique [0002] With the increasingly prominent energy and environmental issues, waste heat power generation, a thermoelectric conversion technology, has received more and more attention as a new energy technology with a wide range of applications and meets the requirements of green environmental protection. It is of great significance for the development of circular economy and the construction of a conservation-oriented society. Ca-Co-O-based oxides are currently widely used high-temperature thermoelectric materials in the industrial field. Ca-Co-O-based oxides have good thermal stability and can work for a long time in a high-temperature oxidizing atmosphere. They are non-toxic and non-polluting. The advantages of good thermal stability, long service life, simple preparation and low cost, especially Ag composite Ca-Co-O-based oxides are the ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the uneven distribution of the Ag phase in the Ag composite Ca-Co-O-based oxide, which is easy to agglomerate, and the Ag phase particle size is large, resulting in the formation of carriers between the Ca-Co-O-based oxide grains Transport loop, the problem of significantly reducing the Seebeck coefficient of Ag composite Ca-Co-O-based oxides, rare earth element doping modification will reduce the conductivity of Ca-Co-O-based oxides, resulting in Ca-Co-O-based oxides There is no significant improvement in the comprehensive thermoelectric properties of oxides, and the oxide thermoelectric material precursor powder prepared by the solid-state method has high reaction temperature, long reaction time, poor chemical uniformity, high energy consumption, and large grain size of oxide thermoelectric materials. defects, and provides a thermoelectric material Ag composite (Ca 1-X La X ) 3 co 4 o 9 preparation method

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