Title :

Lowering thermal conductivity in thermoelectric Ti2−xNiCoSnSb half Heusler high entropy alloys

Author(s) :

Mishra, Soumya Ranjan [Auteur]
Nanyang Technological University [Singapour]
Indian Institute of Technology Madras [IIT Madras]
Karati, Anirudha [Auteur]
Indian Institute of Technology Madras [IIT Madras]
International Advanced Research Centre for powder metallurgy and new materials [ARCI]
Ghosh, Sanyukta [Auteur]
Indian Institute of Science [Bangalore] [IISc Bangalore]
Mallik, Ramesh Chandra [Auteur]
Indian Institute of Science [Bangalore] [IISc Bangalore]
Shabadi, Rajashekhara [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207
Krishnan, P. S. Sankara Rama [Auteur]
Nanyang Technological University [Singapour]
Yadav, Satyesh Kumar [Auteur]
Indian Institute of Technology Madras [IIT Madras]
Ramanujan, R. V. [Auteur]
Nanyang Technological University [Singapour]
Murty, B. S. [Auteur]
Indian Institute of Technology Madras [IIT Madras]
Indian Institute of Technology [Hyderabad] [IIT Hyderabad]

Journal title :

Journal of Materials Science

Abbreviated title :

J Mater Sci

Volume number :

58

Pages :

10736-10752

Publisher :

Springer Science and Business Media LLC

Publication date :

2023-06-26

ISSN :

0022-2461

HAL domain(s) :

Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
Chimie/Matériaux

English abstract : [en]

Ti2−xNiCoSnSb (x = 0.125, 0.250, 0.375, and 0.500) half Heusler (HH) high-entropy thermoelectric alloys were synthesized by the arc melting—ball milling—spark plasma sintering route. The impact of secondary phase content ...
Show more >Ti2−xNiCoSnSb (x = 0.125, 0.250, 0.375, and 0.500) half Heusler (HH) high-entropy thermoelectric alloys were synthesized by the arc melting—ball milling—spark plasma sintering route. The impact of secondary phase content on the thermoelectric properties in these alloys was examined. Ni-rich intermetallic (Ni3Sn2, Ni3Sn4) compounds were observed; the intermetallic content increased for lower Ti content, e.g., Ti1.5NiCoSnSb. A Ni-rich full Heusler (FH) secondary phase was also observed. These results were consistent with first-principles calculations that show that the formation enthalpy of Ti1.5NiCoSnSb was higher than that of Ti2NiCoSnSb and the full Heusler (FH) TiNi2Sn phase. In lower Ti content samples, the electrical conductivity increased, and lattice thermal conductivity decreased at the expense of thermopower owing to higher FH and the Ni3Sn2 phase content. Ti1.5NiCoSnSb exhibited lower lattice thermal conductivity of 3.5 W/mK, compared to 5.4 W/mK at 823 K for Ti2NiCoSnSb due to increased phonon scattering at HH/Ni3Sn2 interfaces. But considering the decreasing power factor with lower Ti content, the maximum ZT obtained in Ti1.875NiCoSnSb (0.171 at 973 K) was only marginally higher than the value for Ti2NiCoSnSb. Further, compositional tuning is hence necessary to maximize the power factor.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Other project(s) or funding source(s) :

AME Programmatic Fund by the Agency for Science, Technology and Research, Singapore under Grant No. A1898b0043 and A18B1b0061

Administrative institution(s) :

Université de Lille
CNRS
INRAE
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Métallurgie Physique et Génie des Matériaux

Submission date :

2024-01-15T14:25:28Z
2024-01-26T15:06:53Z