Giant Thermoelectric Efficiency of Single-Filled Skutterudite Nanocomposites: Role of Interface Carrier Filtering

Trivedi, Vikrant and Tiadi, Minati and Murty, B S and et al, . (2022) Giant Thermoelectric Efficiency of Single-Filled Skutterudite Nanocomposites: Role of Interface Carrier Filtering. ACS Applied Materials & Interfaces, 14 (45). pp. 51084-51095. ISSN 1944-8244

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Abstract

The advantage of secondary-phase induced carrier filtering on the thermoelectric properties has paved the way for developing cost-effective, highly efficient thermoelectric materials. Here, we report a very high thermoelectric figure-of-merit of skutterudite nanocomposites achieved by tailoring interface carrier filtering. The single-filled skutterudite nanocomposites are prepared by dispersing rare-earth oxides nanoparticles (Yb2O3, Sm2O3, La2O3) in the skutterudite (Dy0.4Co3.2Ni0.8Sb12) matrix. The nanoparticles/skutterudite interfaces act as efficient carrier filters, thereby significantly enhancing the Seebeck coefficient without compromising the electrical conductivity. As a result, the highest power factor of similar to 6.5 W/mK2 is achieved in the skutterudite nanocomposites. The nonuniform strain distribution near the nanoparticles due to the local lattice misfit and concentration fluctuations affect the heat carriers and thereby reduce the lattice thermal conductivity. Moreover, the three-dimensional atom probe analysis reveals the formation of Ni-rich grain boundaries in the skutterudite matrix, which also facilitates the reduction of lattice thermal conductivity. Both the factors, i.e., the reduction in lattice thermal conductivity and the enhancement of the power factor, lead to an enormous increase in ZT up to similar to 1.84 at 723 K and an average ZT of about 1.56 in the temperature range from 523 to 723 K, the highest among the single-filled skutterudites reported so far.

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IITH Creators:

IITH Creators	ORCiD
Murty, B S	https://orcid.org/0000-0002-4399-8531

Item Type:

Article

Additional Information:

The authors are thankful to the Director, ARCI, and Prof. G. Sundararajan, Distinguished Scientist, ARCI, for their con-tinuous support. V.T., M.T., M.B., and R.G. are also grateful to the Department of Science and Technology (DST) , India, for the financial support through a research grant (No. AI/1/65/ARCI/2014) . D.K.S. acknowledges financial support from the Ministry of Human Resource and Developments (MHRD) , India through IMPRINT project (No. PHY/16-17/330/MIMP/DILI) . The authors thank Dr. K. Suresh of ARCI for helping in APT measurements at the National Facility for Atom Probe Facility (NFAPT) , IIT Madras.

Uncontrolled Keywords:

SCATTERING,FIGURE,POWER,ZT

Subjects:

Materials Engineering > Materials engineering

Divisions:

Department of Material Science Engineering

Depositing User:

Mr Alauddin Shan Khan

Date Deposited:

25 Nov 2022 07:12

Last Modified:

25 Nov 2022 07:12