The p-type Te-free Cu_(3)SbSe_(4)with famatinite structure is a potential candidate for thermoelectric materials due to the low cost and eco-friendly constituent elements.However,its strong bipolar effect and high lat...The p-type Te-free Cu_(3)SbSe_(4)with famatinite structure is a potential candidate for thermoelectric materials due to the low cost and eco-friendly constituent elements.However,its strong bipolar effect and high lattice thermal conductivity(klat)are the main challenges for its performance enhancement.Herein,we report a new strategy to enhance its figure of merit zT~0.86 at 673 K for Cu_(3)Sb_(0.95)Fe_(0.05)Se_(2.8)S_(1.2)via band structure tuning and hierarchical architecture.Firstly,S substituted Se atoms in lattice can widen the band gap to alleviate the bipolar effect.Secondly,Fe doping in Sb site significantly increases the density of states,thus increasing the carrier effective mass,and obtaining a remarkably high Seebeck coefficient of~560 mV/K at 300 K.Moreover,the induced hierarchical architecture defects resulting in a minimum klat of~0.48 W·m^(-1)·K^(-1)at 673 K.Consequently,the improved Seebeck coefficient combined with low thermal conductivity leads to an enhanced zT.展开更多
基金supported by the National Natural Science Foundation of China(51572111,52172090)the Natural Science Foundation(BK20210779)+1 种基金the University-Industry Research Cooperation Project(BY20221151)the Universities Natural Science Research Project(21KJB430019)of Jiangsu Province.
文摘The p-type Te-free Cu_(3)SbSe_(4)with famatinite structure is a potential candidate for thermoelectric materials due to the low cost and eco-friendly constituent elements.However,its strong bipolar effect and high lattice thermal conductivity(klat)are the main challenges for its performance enhancement.Herein,we report a new strategy to enhance its figure of merit zT~0.86 at 673 K for Cu_(3)Sb_(0.95)Fe_(0.05)Se_(2.8)S_(1.2)via band structure tuning and hierarchical architecture.Firstly,S substituted Se atoms in lattice can widen the band gap to alleviate the bipolar effect.Secondly,Fe doping in Sb site significantly increases the density of states,thus increasing the carrier effective mass,and obtaining a remarkably high Seebeck coefficient of~560 mV/K at 300 K.Moreover,the induced hierarchical architecture defects resulting in a minimum klat of~0.48 W·m^(-1)·K^(-1)at 673 K.Consequently,the improved Seebeck coefficient combined with low thermal conductivity leads to an enhanced zT.
