Alloys and Compounds for Thermoelectric and Solar Cell Applications X: Poster Session
Sponsored by: TMS Structural Materials Division, TMS Functional Materials Division, TMS: Alloy Phases Committee
Program Organizers: Hsin-Jay Wu, National Chiao Tung University; Sinn-wen Chen, National Tsing Hua University; Franck Gascoin, CNRS Crismat Unicaen; Philippe Jund, Montpellier University; Yoshisato Kimura, Tokyo Institute of Technology; Takao Mori, National Institute For Materials Science; Alexandra Zevalkink, Michigan State University; Wan-Ting Chiu, Tokyo Institute of Technology; Pai-chun Wei, National Taiwan University
Monday 5:30 PM
February 28, 2022
Room: Exhibit Hall C
Location: Anaheim Convention Center
NOW ON-DEMAND ONLY - C-1: Flexible n-type Chalcopyrite/PEDOT:PSS/Graphene Hybrid Film for Thermoelectric Device Harvesting Low Grade Heat: Yanan Wang1; Hong Pang1; Quansheng Guo1; Naohito Tsujii1; Takao Mori1; 1National Institute for Materials Science
Combining inorganic thermoelectric materials with conductive polymers is one promising strategy in flexible thermoelectric (FTE) films and devices community. As the inorganic thermoelectric fillers tried up to now have been constituted of scarce or toxic elements and most FTE materials are p-type, we explored the Zn-doped chalcopyrite as inorganic fillers for flexible n-type FTE films. We fabricated the films from custom-design of Cu1-xZnxFeS2/PEDOT:PSS to optimum-design of Cu0.98Zn0.02FeS2/PEDOT:PSS/graphene by drop-casting method assisted with cold-pressing. TE properties elucidate that, compared with binary film, a 4-fold enhancement on electrical conductivity was observed in ternary film, leading to an enhancement in power factor. The ternary film preserves > 80% of the electrical conductivity after 2000 bending times. A five-leg thermoelectric prototype was made of optimum ternary films, generating a voltage of 4.8 mV at ΔT = 6.5℃. Such an evolution of an inexpensive chalcopyrite-based composite film exhibits potential for wearable TE energy conversion applications.
C-2: Ternary Phase Diagram and Thermoelectric Performance of Bi-doped GeTe: Bo-Chia Chen1; Kuang-Kuo Wang2; Hsin-Jay Wu1; 1National Yang Ming Chiao Tung University; 2National Sun Yat-sen University
The relationship between phase, microstructure, and transport properties can be guided by phase diagram engineering, which can investigate the high-performance thermoelectric (TE) alloys. While pristine GeTe possesses high thermal conductivity , Ge1-xBixTe alloys decreased ~ 85% to 1.2 Wm-1K-1 at 323 K. The strongly lattice distortion and high-density stacking faults were revealed by synchrotron XRD and TEM analysis, which were the main reasons for the huge reduction of . Besides the reduction of , Bi as substitution also declined the carrier concentration from 9.5 ×10^20 to 2×10^20 (cm-3) simultaneously. In summary, doping Bi instead of alloying with Bi2Te3 or Bi4Te3 in GeTe induced rhombohedral distortion, leading to low . Therefore, Ge0.9Bi0.1Te boost peak zT from 0.7 to 1.9 at 713 K.