Cu-and Ag-based superionic conductors are promising thermoelectric materials due to their good electrical properties and intrinsically low thermal conductivity. However, the poor electrical and thermal stability restr...Cu-and Ag-based superionic conductors are promising thermoelectric materials due to their good electrical properties and intrinsically low thermal conductivity. However, the poor electrical and thermal stability restrict their application. In this work, n-type pure phase Ag_(2) Te compound is synthesized by simply grinding elemental powders at room temperature and compacted by spark plasma sintering. It is found that, because of the migration of Ag+after the phase transition around 425 K, submicron pores are formed inside the samples during the electrical performance measurement, resulting in poor electrical stability and repeatability of Ag_(2) Te samples. However, Pb-doped Ag_(2-x)Pb_(x)Te(x = 0–0.05) specimens exhibit improved electrical stability by the precipitation of the secondary phase Pb Te in the Ag_(2) Te matrix, which is confirmed via cyclic electrical property measurement and microstructure characterization.A maximum z T = 0.72 is obtained at 570 K for x = 0.03 mainly due to the increased power factor.展开更多
Inorganic semiconductor Ag_(2)Te_(1-x)S_(x)has been recently found to exhibit unexpected plastic deformation with compressive strain up to 30%.However,the origin of the abnormal plasticity and how to simultaneously ac...Inorganic semiconductor Ag_(2)Te_(1-x)S_(x)has been recently found to exhibit unexpected plastic deformation with compressive strain up to 30%.However,the origin of the abnormal plasticity and how to simultaneously achieve superb ductility and high mobility are still elusive.Here,we demonstrate that crystalline/amorphous Ag_(2)Te_(1-x)S_(x)(x=0.3,0.4,and 0.5)composites can exhibit excellent compressive strain up to 70%if the monoclinic Ag2Te phase,which commonly exists in the matrix,is eliminated.Significantly,an ultra-high tensile elongation reaching 107.3%was found in Ag_(2)TeAg_(2)Te_(0.7)S_(x)S_(0.3),which is the highest one yet reported in the system and even surpasses those achieved in some metals and high-entropy alloys.Moreover,high mobility of above 1000 cm^(2)VAg^(-1)s^(-1) at room temperature and good thermoelectric performance are simultaneously maintained.A modified Ashby plot with ductility factor versus carrier mobility is thereby proposed to highlight the potential of solid materials for applications in flexible/wearable electronics.展开更多
基金financially supported by the National Science Fund for Distinguished Young Scholars (No. 51725102)the Natural Science Foundation of China (Nos. 51871199, 51861145305)。
文摘Cu-and Ag-based superionic conductors are promising thermoelectric materials due to their good electrical properties and intrinsically low thermal conductivity. However, the poor electrical and thermal stability restrict their application. In this work, n-type pure phase Ag_(2) Te compound is synthesized by simply grinding elemental powders at room temperature and compacted by spark plasma sintering. It is found that, because of the migration of Ag+after the phase transition around 425 K, submicron pores are formed inside the samples during the electrical performance measurement, resulting in poor electrical stability and repeatability of Ag_(2) Te samples. However, Pb-doped Ag_(2-x)Pb_(x)Te(x = 0–0.05) specimens exhibit improved electrical stability by the precipitation of the secondary phase Pb Te in the Ag_(2) Te matrix, which is confirmed via cyclic electrical property measurement and microstructure characterization.A maximum z T = 0.72 is obtained at 570 K for x = 0.03 mainly due to the increased power factor.
基金supported by the National Science Fund for Distinguished Young Scholars(no.51725102)the National Natural Science Foundation of China(nos.92163203 and 52101275)+1 种基金the Key Research and Development Program of Zhejiang Province(2022C01131 and 2021C01026)Zhejiang Provincial Natural Science Foundation of China(no.LD22E020005).
文摘Inorganic semiconductor Ag_(2)Te_(1-x)S_(x)has been recently found to exhibit unexpected plastic deformation with compressive strain up to 30%.However,the origin of the abnormal plasticity and how to simultaneously achieve superb ductility and high mobility are still elusive.Here,we demonstrate that crystalline/amorphous Ag_(2)Te_(1-x)S_(x)(x=0.3,0.4,and 0.5)composites can exhibit excellent compressive strain up to 70%if the monoclinic Ag2Te phase,which commonly exists in the matrix,is eliminated.Significantly,an ultra-high tensile elongation reaching 107.3%was found in Ag_(2)TeAg_(2)Te_(0.7)S_(x)S_(0.3),which is the highest one yet reported in the system and even surpasses those achieved in some metals and high-entropy alloys.Moreover,high mobility of above 1000 cm^(2)VAg^(-1)s^(-1) at room temperature and good thermoelectric performance are simultaneously maintained.A modified Ashby plot with ductility factor versus carrier mobility is thereby proposed to highlight the potential of solid materials for applications in flexible/wearable electronics.
