Advancement of thermoelectric performances through the dispersion of expanded graphene on p-type BiSbTe alloys

ABSTRACT

We demonstrated the systematic investigation of the graphene addition on the microstructural behaviour and concurrent thermoelectric properties of water-atomized p-type BiSbTe (BST)- based alloy using mechanical ball milling, and followed through the spark plasma sintering to fabricate a bulk compact specimen. X-ray diffraction results confirm the single phase of BST. The fracture surface of both specimen exhibits the homogenous distribution of grains with irregular shapes in a random alignment. The graphene in the BST provides an extra carrier transport leading to an increment in the carrier concentration (n) resulting in higher electrical conductivity (σ) for the BST + Graphene composite. The interface between two-dimensional (2D) graphene and bulk BST provides a larger degree of phonon scattering leading to a maximum reduced thermal conductivity (к) of 0.8 W m⁻¹K⁻¹ compared to pristine- BST (0.9 W m⁻¹K⁻¹) results in a maximum figure of merit (ZT) 1.1 at 400 K.

KEYWORDS:

• Water-atomization
• mechanical ball milling
• BiSbTe alloy
• graphene
• thermal conductivity (к)

Acknowledgement

This work was supported by a research grant from the Kongju National University in 2022.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Kongju National University [grant number 2022].

Notes on contributors

Eun-Ha Go

Eun-Ha Go is currently doing her master's course in Advanced Materials Engineering at Kongju National University, Republic of Korea after completing her bachelor's degree in Advanced Materials Engineering in 2022. She is interested in thermoelectric materials specifically the fabrication of nanostructured powders and studying their thermoelectric and mechanical properties for power generation.

Rathinam Vasudevan

Rathinam Vasudevan is a Postdoctoral Researcher at Kongju National University, Republic of Korea. He received his Ph.D. in Materials Science from Anna University, India in 2013 and later, he worked as a Postdoctoral Research Fellow in Academia Sinica, Taiwan from 2015 to 2018, and continued at Shanghai Jiao Tong University, China from 2019 to 2022. His main research interests are thermoelectric materials, particularly in the alloying of intermetallic compounds and layered metal chalcogenides for energy conversions.

Babu Madavali

Babu Madavali received his Ph.D. degree in Advanced Materials Engineering from Kongju National University, Republic of Korea, in 2016. He was a BK21 Postdoctoral Researcher, followed by a Senior Postdoctoral Researcher at the Center for Advanced Materials and Parts of Powders (CAMP²) in Kongju National University. His major research interests are in the development of functional and structural materials using powder metallurgy especially, rapid solidification processes such as gas atomization, and water atomization followed by different sintering techniques. Currently, he is working as a Postdoctoral Researcher at the National Institute for Materials Science (NIMS), Japan, and focusing his research on Spin caloritronic, and Functional magnetic materials.

Peyala Dharmaiah

Peyala Dharmaiah obtained his Ph.D. in Materials Science and Engineering from Kongju National University, Republic of Korea, where he focused on the synthesis and characterization of thermoelectric materials under the supervision of Prof. Soon-Jik Hong. His primary research interests are the electronic and phonon transport properties as well as the synthesis of various types of thermoelectric materials for energy harvesting applications. He is currently pursuing research on two-dimensional (2D) layered Zintl phase materials as a Postdoctoral Fellow at the Korea Institute of Science and Technology (KIST).

Min-Woo Shin

Min-Woo Shin finished his master's course in Advanced Materials Engineering from Kongju National University, Republic of Korea in 2023. His research interests focus on the fabrication of high entropy powders and studying their wear and mechanical properties for various applications.

Sung Ho Song

Sung Ho Song is an Associate Professor at Kongju National University, Republic of Korea. He obtained his Ph.D. in Materials Science and Engineering from the Korea Advanced Institute of Science and Technology (KAIST), Republic of Korea in 2015. He worked as a Postdoctoral Researcher at KAIST in 2015 and as a Research Fellow at the Institute for Basic Science, Republic of Korea from 2015 to 2016. Prior to his Ph.D., he worked at NEXEN TIRE Central Research Institute from 2007 to 2010. His research mainly focuses on low-dimensional nanomaterials (Quantum Dots, Graphene, CNT, Nanowire, TMDCs (MoS₂, BN)), manufacturing and application of 3D nanostructures, and multidimensional hybrid materials, Energy and Display devices.

Soon-Jik Hong

Soon-Jik Hong is a Professor at Kongju National University, Republic of Korea, and Head of the Center for Advanced Materials and Parts of Powders (CAMP²) since 2021. He received his Ph.D. in Materials Engineering from Chungnam National University, Republic of Korea in 2001. He worked as a Postdoctoral Fellow at the University of Central Florida (USA) from 2003 to 2005 and as a Researcher at Korea Atomic Energy Research Institute (KAERI) from 2005 to 2006. He was also an Exchange Researcher at the University of Oxford (UK) from 1998 to 1999. He has held several research positions and is a member of various research committees in the Republic of Korea. His research interests include the synthesis and processing of micro and nanopowders for various applications particularly dealing with Al-Si and high entropy structural materials, hard magnetic materials, and thermoelectric materials for energy conversion technologies.