摘要
Element doping and nano-inclusion embedding are effective approaches to enhance the electrical conductivities and decrease the lattice thermal conductivities of thermoelectric(TE)materials,respectively.However,the intrinsic low electrical thermal conductivities and high electrical properties are severely sacrificed,and the final figure of merit(ZT)is usually restricted.In this study,Ag doping and Pt quantum dot(QD)embedding were synchronously achieved via embedding Ag/Pt alloy QDs into the higher manganese silicides to avoid the conventional single-element doping strategy.The power factor(at 823 K)was enhanced from 1.57×10^(-3) W m^(-1) K^(-2) to 1.82×10^(-3) W m^(-1) K^(-2)(-16%)due to the-18%increase in carrier concentration that was derived from the Ag doping effect.Simultaneously,the lattice thermal conductivity(at 823 K)decreased from 2.65 W m^(-1) K^(-1) e1.92 W m^(-1) K^(-1)(-28%)because of the broadband phonon scattering effect that resulted from the residual Pt QDs inclusions.Synthetically,the optimal ZT value increased by-52%from 0.42 to 0.64 at 823 K.This study demonstrated that incorporating metastable alloy QDs to obtain element doping and nano-inclusion embedding effects is a novel and feasible means to enhance the ZT value of HMS.This method is also possibly applicable to other alloy QD/TE composites.
基金
supported by the National Science Foundation for Young Scientists of China(51802071)
Advanced Talents Incubation Program of the Hebei University(521000981162)
Outstanding Youth Science Foundation project of Hebei Province(A2020201032)
Local Science and Technology Development Fund Projects Guided by the Central Government(206Z4403G)
National Natural Science Foundation of China(No.51372064)
Hebei Province High-level Talents Funding project(No.A201801003).
作者简介
Qing Wang is currently a Ph.D.candidate in the College of physics Science and Technology,Hebei University,China.She received her bachelor’s degree and finished the master’s studies at College of physics Science and Technology,Hebei University.Her current researches focus on the HMS based materials and thermoelectric propertie;Shiyu Song is currently a master’s degree candidate at the College of physics Science and Technology,Hebei University,China.She received her bachelor’s degree from College of Mathematics and Physics,Bohai University,China.Her current research interests focus on the nanomaterials and thermoelectric properties;Xiaofeng Yang is currently a master’s degree candidate at the College of physics Science and Technology,Hebei University,China.She received her bachelor’s degree from Department of Physics,Lvliang University,China.Her current research interests focus on the nanomaterials and thermoelectric properties;Dr.Xingyuan San graduated from Kunming University of Science and Technology in 2011,and received his Ph.D.from University of Chinese Academy of Sciences in 2017.He is currently a lecturer of Physics Science and Technology at Hebei University,China.Research interests:Transmission Electron Microscopy and the Applications in Materials Science.He is especially interested in analyzing and understanding the defect structures of solid state materials and interfaces at atomic level;Dr.Jianglong Wang is currently a professor at College of Physics Science and Technology,Hebei University,China.He received his Ph.D.from Institute of Solid State Physics,Chinese Academy of Sciences in 2004.His current research interests focus on the first principles modeling of thermoelectric materials;Corresponding author:Dr.Dan Zhang is currently a lecturer of Physics Science and Technology at Hebei University,China.He received his Ph.D.from Huazhong University of Science and Technology in 2017.His research interests focus on thermoelectric materials and DFT calculation.E-mail addresses:sfwang@hbu.edu.cn;Corresponding author:Dr.Shu-fang Wang received her Ph.D.from the Institute of Physics,Chinese Academy of Sciences in 2004.She then joined in the group of Professor D.Remiens at IEMN-CNRS,France as a postdoctoral fellow and after that joined in the group of Professor Xiaoxing Xi at the Penn.State University as a postdoctoral fellow.She is currently a full professor and a group leader at Hebei University of China.Her researches focus on the fields of photoelectric/thermoelectric materials and devices,danzhang@hbu.edu.cn;Corresponding author:Dr.Zhiliang Li is currently an associate professor and employed professor at College of Physics Science and Technology,Hebei University,China.He finished his postdoctoral study at School of Materials Science and Engineering,Tsinghua University in 2017.He received his Ph.D.from Department of Materials Science and Engineering,China University of Petroleum,Beijing,in 2015.He specializes in the studies of solution phase chemistry,nano-technology and thermoelectric materials.,phd-lzl@hbu.edu.cn。
