We report a greatly enhanced thermoelectric performance in a BiCuSeO system, realized by improving carrier mobility through modulation doping. The heterostructures of the modulation doped sample make charge carriers transport preferentially in the low carrier concentration area, which increases carrier mobility by a factor of 2 while maintaining the carrier concentration similar to that in the uniformly doped sample. The improved electrical conductivity and retained Seebeck coefficient synergistically lead to a broad, high power factor ranging from 5 to 10 μW cm(-1) K(-2). Coupling the extraordinarily high power factor with the extremely low thermal conductivity of ∼0.25 W m(-1) K(-1) at 923 K, a high ZT ≈ 1.4 is achieved in a BiCuSeO system.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/ja507945h | DOI Listing |
Small Methods
October 2024
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China.
BiCuSeO is a promising oxygen-containing thermoelectric material due to its intrinsically low lattice thermal conductivity and excellent service stability. However, the low electrical conductivity limits its thermoelectric performance. Aliovalent element doping can significantly improve their carrier concentration, but it may also impact carrier mobility and thermal transport properties.
View Article and Find Full Text PDFMaterials (Basel)
June 2023
College of Science/Xinjiang Production & Construction Corps Key Laboratory of Advanced Energy Storage Materials and Technology, Shihezi University, Shihezi 832000, China.
Based on the first-principles calculations, the electronic structure and transport properties of BiMChO (M=Cu and Ag, Ch=S, Se, and Te) superlattices have been studied. They are all semiconductors with indirect band gaps. The increased band gap and decreased band dispersion near the valence band maximum (VBM) lead to the lowest electrical conductivity and the lowest power factor for -type BiAgSeO/BiCuSeO.
View Article and Find Full Text PDFResearch (Wash D C)
April 2023
Information Materials and Intelligent Sensing Laboratory of Anhui Province, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology and School of Materials Science and Engineering, Anhui University, Hefei 230601, China.
Seeking new strategies to tune the intrinsic defect and optimize the thermoelectric performance via no or less use of external doped elements (i.e., plain optimization) is an important method to realize the sustainable development of thermoelectric materials.
View Article and Find Full Text PDFNat Commun
April 2023
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China.
Thermoelectric materials can realize direct conversion between heat and electricity, showing excellent potential for waste heat recovery. CuSe is a typical superionic conductor thermoelectric material having extraordinary ZT values, but its superionic feature causes poor service stability and low mobility. Here, we reported a fast preparation method of self-propagating high-temperature synthesis to realize in situ compositing of BiCuSeO and CuSe to optimize the service stability.
View Article and Find Full Text PDFAcc Chem Res
October 2022
Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States.
ConspectusThermoelectric (TE) materials have received much attention because of their ability to convert heat energy to electrical energy. At a given temperature , the efficiency of a TE material for this energy conversion is measured by the figure of merit , which is related to the thermopower (or Seebeck coefficient) , the thermal conductivity κ, and the electrical conductivity σ of the TE material as = (σ)/κ. BiQ and PbQ (Q = Se, Te) are efficient TE materials with high , although they are not ecofriendly and their stability is poor at high temperature.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!