Full-scale computation for all the thermoelectric property parameters of half-Heusler compounds

نویسندگان

  • A. J. Hong
  • L. Li
  • R. He
  • J. J. Gong
  • Z. B. Yan
  • K. F. Wang
  • J. -M. Liu
  • Z. F. Ren
چکیده

The thermoelectric performance of materials relies substantially on the band structures that determine the electronic and phononic transports, while the transport behaviors compete and counter-act for the power factor PF and figure-of-merit ZT. These issues make a full-scale computation of the whole set of thermoelectric parameters particularly attractive, while a calculation scheme of the electronic and phononic contributions to thermal conductivity remains yet challenging. In this work, we present a full-scale computation scheme based on the first-principles calculations by choosing a set of doped half-Heusler compounds as examples for illustration. The electronic structure is computed using the WIEN2k code and the carrier relaxation times for electrons and holes are calculated using the Bardeen and Shockley's deformation potential (DP) theory. The finite-temperature electronic transport is evaluated within the framework of Boltzmann transport theory. In sequence, the density functional perturbation combined with the quasi-harmonic approximation and the Klemens' equation is implemented for calculating the lattice thermal conductivity of carrier-doped thermoelectric materials such as Ti-doped NbFeSb compounds without losing a generality. The calculated results show good agreement with experimental data. The present methodology represents an effective and powerful approach to calculate the whole set of thermoelectric properties for thermoelectric materials.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Synthesis and Thermoelectric Properties of Ni-Doped ZrCoSb Half-Heusler Compounds

The Ni-doped ZrCo1−xNixSb half-Heusler compounds were prepared by arc-melting and spark plasma sintering technology. X-ray diffraction analysis results showed that all samples were crystallized in a half-Heusler phase. Thermoelectric properties of ZrCo1−xNixSb compounds were measured from room temperature to 850 K. The electrical conductivity and the absolute value of Seebeck coefficient increa...

متن کامل

Effect of C and N Addition on Thermoelectric Properties of TiNiSn Half-Heusler Compounds

We investigated the thermoelectric properties of the ternary half-Heusler compound, TiNiSn, when introducing C and N. The addition of C or N to TiNiSn leads to an enhanced power factor and a decreasing lattice thermal conductivity by point defect phonon scattering. The thermoelectric performances of TiNiSn alloys are significantly improved by adding 1 at. % TiN, TiC, and figure of merit (ZT) va...

متن کامل

Resolving the true band gap of ZrNiSn half-Heusler thermoelectric materials

Band structure parameters, such as the band gap, can be estimated using electrical transport properties. In many thermoelectric studies, the temperature dependent Seebeck coefficient is used to estimate the band gap using the Goldsmid–Sharp band gap formula: Eg 1⁄4 2eSmaxTmax. This important, fundamental parameter is useful for characterizing and understanding any semiconductor, but it is parti...

متن کامل

Theory of Heusler and Full-Heusler compounds

Spintronics/magnetoelectronics brought at the center of scientific research the Heusler and full-Heusler compounds, since several among them have been shown to be half-metals. In this review we present a study of the basic electronic and magnetic properties of both Heusler families; the so-called semi-Heusler alloys like NiMnSb and the full-Heusler alloys like Co2MnGe (usual full-Heuslers), Mn2...

متن کامل

Invitation to the public defense of the doctoral thesis Nanostructured Sb-based Half-Heusler alloys (p-type): Phase equilibria, thermoelectric properties at low and high temperature, and mechanical properties

In search of new highly efficient and mechanically robust thermoelectric materials, the investigations of this thesis focused on the phase structure, the thermoelectric efficiency (“figure of merit” ZT), and mechanical properties of two p-type Half-Heusler (HH) alloys, i.e. several TiFeSb alloys with Ti/Fe, Fe/Co and Sb/Sn substitutions, and a series of NbFeSb alloys doped in the Nb site with g...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 6  شماره 

صفحات  -

تاریخ انتشار 2016