title: Boundary Engineering for the Thermoelectric Performance of Bulk Alloys Based on Bismuth Telluride.
abstract: Thermoelectrics, which transports heat for refrigeration or converts heat into electricity directly, is a key technology for renewable energy harvesting and solid-state refrigeration. Despite its importance, the widespread use of thermoelectric devices is constrained because of the low efficiency of thermoelectric bulk alloys. However, boundary engineering has been demonstrated as one of the most effective ways to enhance the thermoelectric performance of conventional thermoelectric materials such as Bi2 Te3 , PbTe, and SiGe alloys because their thermal and electronic transport properties can be manipulated separately by this approach. We review our recent progress on the enhancement of the thermoelectric figure of merit through boundary engineering together with the processing technologies for boundary engineering developed most recently using Bi2 Te3 -based bulk alloys. A brief discussion of the principles and current status of boundary-engineered bulk alloys for the enhancement of the thermoelectric figure of merit is presented. We focus mainly on (1) the reduction of the thermal conductivity by grain boundary engineering and (2) the reduction of thermal conductivity without deterioration of the electrical conductivity by phase boundary engineering. We also discuss the next potential approach using two boundary engineering strategies for a breakthrough in the area of bulk thermoelectric alloys.
authors.affiliation: Department of Energy Science, Sungkyunkwan University, Suwon 440-476 (Korea).|Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-476 (Korea).
authors.forename: Hyeona
authors.initials: H
authors.lastname: Mun
authors.affiliation: School of Energy, Materials and Chemical Engineering, Korea University of Technology and Education, Cheonan 330-708 (Korea).
authors.forename: Soon-Mok
authors.initials: SM
authors.lastname: Choi
authors.affiliation: Department of Nano Applied Engineering, Kangwon National University, Chuncheon 200-701 (Korea). khlee2014@kangwon.ac.kr.
authors.forename: Kyu Hyoung
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Department of Energy Science, Sungkyunkwan University, Suwon 440-476 (Korea). kimsungwng@skku.edu.|Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-476 (Korea). kimsungwng@skku.edu.
authors.forename: Sung Wng
authors.initials: SW
authors.lastname: Kim
mesh_terms: D000497:Alloys; D001729:Bismuth / Q000737:chemistry*; D004560:Electricity; D004738:Engineering / Q000379:methods*; D013691:Tellurium / Q000737:chemistry*; D013696:Temperature
chemical_list: D000497:Alloys; C542787:bismuth telluride; D013691:Tellurium; D001729:Bismuth
keywords: alloys; bismuth; materials science; nanoparticles; tellurium