| AVS 66th International Symposium & Exhibition | |
| Thin Films Division | Thursday Sessions |
| Session TF+EM+NS+SS-ThM |
| Session: | Thin Films for Energy Harvesting and Conversion |
| Presenter: | Eshirdanya McGhee, Alabama A&M University |
| Authors: | E. McGhee, Alabama A&M University S. Budak, Alabama A&M University Z. Xiao, Alabama A&M University N. Caver, Alabama A&M University B. McNeal, Alabama A&M University |
| Correspondent: | Click to Email |
The thermoelectric (TE) concept could be seen as a perfect solution for recovering waste heat from engine exhaust and converts in to electric energy. TE generators are all solid-state devices that convert heat into electricity. Unlike traditional dynamic heat engines, TE generators contain no moving parts and are completely silent. Such generators have been used reliably for over 30 years of maintenance-free operation in deep space probes such as the Voyager missions of NASA. TE systems can be easily designed to operate with small heat sources and small temperature differences [1]. An ideal TE material behaves like an electron crystal and phonon glass, allowing a large temperature gradient across it while conducting electricity efficiently to generate a TE voltage. Significant progress in the TE performance of materials has been made by exploring ultra low thermal conductivity at high temperature and reducing thermal conductivity by nano-structuring, as well as by resonant doping and energy-dependent scattering of electrons [2]. The figure of merit ZT describes material performance. ZT depends on the thermoelectric material properties of Seebeck coefficient S, electrical conductivity σ, and thermal conductivity K, and ZT=S2σT/K where T is the temperature of the material [3]. TE devices from 50 alternating layers of Sb/Sb+SnO2 thin films were prepared by DC/RF Magnetron Sputtering. TE devices were annealed at different temperatures to form nano-structures to increase the Seebeck coefficients and electrical conductivity and decrease thermal conductivity. For the characterization, Seebeck coefficient, van der Pauw resistivity, and thermal conductivity were used. The surface morphology was characterized using SEM/EDS.
[1] Krishna Purohit, Sheetal Kumar Jain, Dr. P M Meena, Khushaboo Singh, Manish Dadhich,
“Review Paper on Optimizations of Thermoelectric System”, International Journal of Innovative Research in Engineering & Management (IJIREM), ISSN: 2350-0557, Volume-3, Issue-4, (July-2016), 259-263.
[2] Kedar Hippalgaonkar, Ying Wang, Yu Ye, Diana Y. Qiu, Hanyu Zhu, Yuan Wang, Joel Moore, Steven G. Louie, and Xiang Zhang, “High thermoelectric power factor in two-dimensional crystals of MoS2”, PHYSICAL REVIEW B 95, 115407 (2017) 1-9.
[3] Saniya LeBlanc, Sustainable Materials and Technologies 1–2 (2014) 26–35.
Acknowledgement
Research was sponsored by NSF with grant numbers NSF-HBCU-RISE-1546965, NSF-EPSCOR-R-II-3-EPS-1158862, NSF-MRI-1337616, DOD with grant numbers W911 NF-08-1-0425, and W911NF-12-1-0063, U.S. Department of Energy National Nuclear Security Administration (DOE-NNSA) with grant numbers DE-NA0001896 and DE-NA0002687.