Method for ultra-rapidly preparing Ag<2>X bulk thermoelectric materials

Abstract

The invention discloses a method for ultra-rapidly preparing Ag<2>X (X=Se, Te) bulk thermoelectric materials for the first time. The method uses Ag powder and Se or Te powder as raw materials, firstly, the raw materials are simply mixed uniformly, the obtained mixed raw materials are loaded in a graphite mould, the mould is placed into plasma activation sintering equipment, the densified Ag<2>X bulk thermoelectric materials are prepared in a plasma activation stage of a plasma activation sintering process, and the reaction synthesis and densification process of the Ag<2>X compounds are completed in one step. The process involved in the method provided by the invention is ultra-simple, the preparation time is ultra-short, and the prepared Ag<2>X bulk thermoelectric materials have excellentperformance, and lay a good foundation for large-scale preparation and large-scale application of the Ag<2>X compounds.

Description

technical field [0001] The invention belongs to the technical field of thermoelectric material preparation, in particular to an ultra-fast preparation of Ag 2 X. Approaches to bulk thermoelectric materials. Background technique [0002] Ag 2 X(X=Se,Te) compounds are a kind of extremely important semiconductor materials, which have many peculiar electrical and optical properties, so they have potential application prospects. [0003] Ag 2 Se has two stable solid phases, a low-temperature tetragonal phase (β) and a high-temperature cubic phase (α), and the β-α phase transition temperature is about 407K. β-Ag 2 Se is an n-type semiconductor with a band gap of about 0.07eV at 0K. Ag 2 Te also has two stable solid phases, low-temperature monoclinic phase (β) and high-temperature cubic phase (α), and the β-α transition temperature is about 420K. β-Ag 2 Te is an n-type semiconductor with a forbidden band width of ≤0.2eV at 0K. As a new type of three-dimensional topological...

AI Technical Summary

Problems solved by technology

[0005] Currently, compound Ag 2 Se, Ag 2 The synthesis methods of Te mainly focus on hydrothermal method, solvothermal method, etc., which prepare Ag in solution. 2 Se, Ag 2 Te's method often requires complex reaction process and strict reaction conditions

What's more regrettable is that some toxic chemical reagents need to be used, which consumes time and energy and pollutes the environment

However, the conventional long-term high-temperature melting method and high-temperature solid-state reaction method have strict requirements on equipment, consume energy, and easily cause the absence of Se or Te, making it difficult to precisely control the composition.

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