We try to use Ho doping combined with band modulation to adjust the thermoelectric properties for BiCuSeO.The results show that Ho doping can increase the carrier concentration and increase the electrical conductivity...We try to use Ho doping combined with band modulation to adjust the thermoelectric properties for BiCuSeO.The results show that Ho doping can increase the carrier concentration and increase the electrical conductivity in the whole temperature range.Although Seebeck coefficient decreases due to the increase of carrier concentration,it still keeps relatively high values,especially in the middle and high temperature range.On this basis,the band-modulation sample can maintain relatively higher carrier concentration while maintaining relatively higher mobility,and further improve the electrical transporting performance.In addition,due to the introduction of a large number of interfaces in the band-modulation samples,the phonon scattering is enhanced effectively and the lattice thermal conductivity is reduced.Finally,the maximal power factor(PF)of 5.18μW·cm^(-1)K^-(2)and the dimensionless thermoelectric figure of merits(ZT)of 0.81 are obtained from the 10%Ho modulation doped sample at 873 K.展开更多
With the development of electronic components towards high frequency,high efficiency,and miniaturization,the demand for non-oriented silicon steel ultra-thin ribbons is increasing,which were usually prepared by multi-...With the development of electronic components towards high frequency,high efficiency,and miniaturization,the demand for non-oriented silicon steel ultra-thin ribbons is increasing,which were usually prepared by multi-pass rolling with complex processes and high cost.The ultra-thin non-oriented silicon steel ribbons with silicon content of 2–4.5 wt.%Si were prepared with the planar flow casting technology,and the microstructure and properties of ribbons were investigated.The results showed that as the silicon content increased,the grain size of the as-cast ribbons gradually decreased,and the dislocation density and internal stress were higher.The proportion of{100}oriented grains gradually increased from 29.3 to 37.3%,and the ratio of{110}and{111}oriented grains decreased.Meanwhile,the magnetic induction B50 showed a decline trend from 1.62 to 1.45 T with the increase in silicon content,while the iron loss P_(1.0/400) increased from 20.61 to 66.65 W/kg.This may be related to the silicon content affecting the wettability of melt and the wheel,thereby affecting the cooling capacity.The grains grew significantly after annealing,the internal stress was released and dislocations were eliminated.All this greatly improved the magnetic properties and decreased the hardness.B_(50) of ribbons with 2 wt.%Si reached 1.66 T and P_(1.0/400) of ribbons with 4.5 wt.%Si was reduced to 13.40 W/kg.The percentage of{110}fiber grains increased obviously while{100}fiber grains decreased slightly after heat treatment.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.51674181。
文摘We try to use Ho doping combined with band modulation to adjust the thermoelectric properties for BiCuSeO.The results show that Ho doping can increase the carrier concentration and increase the electrical conductivity in the whole temperature range.Although Seebeck coefficient decreases due to the increase of carrier concentration,it still keeps relatively high values,especially in the middle and high temperature range.On this basis,the band-modulation sample can maintain relatively higher carrier concentration while maintaining relatively higher mobility,and further improve the electrical transporting performance.In addition,due to the introduction of a large number of interfaces in the band-modulation samples,the phonon scattering is enhanced effectively and the lattice thermal conductivity is reduced.Finally,the maximal power factor(PF)of 5.18μW·cm^(-1)K^-(2)and the dimensionless thermoelectric figure of merits(ZT)of 0.81 are obtained from the 10%Ho modulation doped sample at 873 K.
基金supported by the financial support from National Key Research and Development Program of China(No.2021YFB3800501)。
文摘With the development of electronic components towards high frequency,high efficiency,and miniaturization,the demand for non-oriented silicon steel ultra-thin ribbons is increasing,which were usually prepared by multi-pass rolling with complex processes and high cost.The ultra-thin non-oriented silicon steel ribbons with silicon content of 2–4.5 wt.%Si were prepared with the planar flow casting technology,and the microstructure and properties of ribbons were investigated.The results showed that as the silicon content increased,the grain size of the as-cast ribbons gradually decreased,and the dislocation density and internal stress were higher.The proportion of{100}oriented grains gradually increased from 29.3 to 37.3%,and the ratio of{110}and{111}oriented grains decreased.Meanwhile,the magnetic induction B50 showed a decline trend from 1.62 to 1.45 T with the increase in silicon content,while the iron loss P_(1.0/400) increased from 20.61 to 66.65 W/kg.This may be related to the silicon content affecting the wettability of melt and the wheel,thereby affecting the cooling capacity.The grains grew significantly after annealing,the internal stress was released and dislocations were eliminated.All this greatly improved the magnetic properties and decreased the hardness.B_(50) of ribbons with 2 wt.%Si reached 1.66 T and P_(1.0/400) of ribbons with 4.5 wt.%Si was reduced to 13.40 W/kg.The percentage of{110}fiber grains increased obviously while{100}fiber grains decreased slightly after heat treatment.
