A Test Method for Seebeck Coefficient of Thermoelectric Materials

Abstract

The invention discloses a method for testing a Seebeck coefficient of a thermoelectric material. The method integrates characteristics of a steady state method and a dynamic method, and mainly comprises the following steps: I, according to a dynamic testing method, keeping the temperature of a low-temperature end of a sample generally unchanged, rapidly increasing the temperature of a high-temperature end, recording a temperature difference delta T and a potential difference delta U of two ends in real time, and performing linear fitting delta U and delta T into the relationship that delta U=alpha 1*delta T+delta u; II, according to the equation, when delta T=0, acquiring delta U deviation, or when delta U=0, acquiring delta T deviation, and determining the two values as system errors; III, when keeping the average temperature T0 of the sample the temperature difference of two ends unchanged within 5-10K, respectively testing a potential difference delta U0 and a temperature difference delta T0 by using the steady state testing method, and according to an equation that alpha reality=delta U0 / delta T0-delta T deviation=delta U0-delta U deviation / delta T0, introducing delta U deviation or delta T deviation, thereby obtaining alpha reality. By adopting the method, precise testing on the Seebeck coefficient is achieved, system errors introduced in the testing process are eliminated, testing condition requirements are reduced, and very great learning significances can be achieved for making and optimization of data acquisition and processing modes of self-developed, to be developed and conventional commercial equipment.

Description

[0001] Technical field: the invention belongs to the technical field of material electrical performance testing, specifically a method for testing the Seebeck coefficient of thermoelectric materials. Background technique: [0002] Thermoelectric materials have attracted much attention as an important functional material that is expected to solve the current energy and environmental crises facing the world, and their energy conversion efficiency is directly related to the thermoelectric properties of materials. At present, the thermoelectric performance of materials is generally measured by the dimensionless thermoelectric figure of merit ZT, and the expression of ZT is shown in formula 1. [0003] ZT = α 2 ρ -1 kappa -1 T [0004] Where α is the Seebeck coefficient, ρ is the resistivity, κ is the thermal conductivity, and T is the thermodynamic temperature. α, ρ, and κ are physical parameters of materials and are related to temperature. Therefore, it is of great significa...

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However, according to its own assessment, there are errors in both tests

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