6533b829fe1ef96bd128ae60

RESEARCH PRODUCT

Optimization of the carrier concentration in phase-separated half-Heusler compounds

Julia KrezClaudia FelserWilfried HermesJennifer SchmittG. Jeffrey SnyderMarkus Schwind

subject

Materials scienceEffective mass (solid-state physics)Renewable Energy Sustainability and the EnvironmentElectrical resistivity and conductivitySeebeck coefficientThermoelectric effectAnalytical chemistryElectron dopingFigure of meritGeneral Materials ScienceGeneral ChemistryElectronPower factor

description

Inspired by the promising thermoelectric properties of phase-separated half-Heusler materials, we investigated the influence of electron doping in the n-type Ti_(0.3−x)Zr_(0.35)Hf_(0.35)NiSn compound. The addition of Nb to this compound led to a significant increase in its electrical conductivity, and shifted the maximum Seebeck coefficient to higher temperatures owing to the suppression of intrinsic carriers. This resulted in an enhancement of both the power factor α^2σ and figure of merit, zT. The applicability of an average effective mass model revealed the optimized electron properties for samples containing Nb. There is evidence in the literature that the average effective mass model is suitable for estimating the optimized carrier concentration of thermoelectric n-type half-Heusler compounds.

https://doi.org/10.1039/c4ta03000a