Tuning the thermoelectric properties of YNiBi half-Heusler alloy. (20th April 2018)

• Record Type: Journal Article
• Authors: Sharma, Sonu; Kumar, Pradeep
• Is Part Of: Materials research express. Volume 5:Number 4(2018)
• Publication Date: 2018-04-20
• Subjects: half-Heusler alloy -- thermoelectric properties -- power factor -- spin–orbit coupling; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/aabbf1
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: A detail comparison between the results obtained for the electronic and transport properties of YNiBi half-Heusler alloy by local density approximation (LDA) and generalized gradient approximation (GGA) functionals with and without spin–orbit coupling (SOC) is presented. In the presence of SOC both functionals provide ∼30% smaller band gap. The transport coefficients computed without SOC confirm that YNiBi is a promising p-type thermoelectric material. However, with SOC at higher temperature, Seebeck coefficient was found to be negative because of the bipolar effects. Without SOC the computed power factor (PF) is found to be closer to the experimental value, while in the presence of SOC we have obtained comparatively smaller PF. No importance of SOC has been observed in the calculations of transport properties of the compound. The appropriate Ti doping in place of Y is predicted to significantly enhance the thermoelectric properties of YNiBi compound.