Incorporating element doping and quantum dot embedding effects to enhance the thermoelectric properties of higher manganese silicides  

作　　者：Qing Wang Shiyu Song Xiaofeng Yang Ziyang Liu Yufei Ma Xingyuan San Jianglong Wang Dan Zhang Shu-Fang Wang Zhiliang Li 

机构地区：[1]Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province,College of Physics Science and Technology,Hebei University,Baoding,071002,China [2]Institute of Life Science and Green Development,Hebei University,Baoding,071002,China

出　　处：《Journal of Materiomics》2021年第2期377-387,共11页无机材料学学报（英文）

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).

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.

关 键 词：Quantum dot Inclusion Higher manganese silicide Thermoelectric material Figure of merit 

分 类 号：TB34[一般工业技术—材料科学与工程]