Zn掺杂n型笼合物Ba8Ga16-2xZnxGe30+x的热电传输特性

用高温熔融结合放电等离子烧结法制备了Zn掺杂单相n型Ba₈Ga_16-2xZn_xGe_30+x笼合物，探索了Zn对Ga的取代对其热电传输特性的影响规律.研究结果表明,n型Ba₈Ga_16-2xZn_xGe_30+x化合物的电导率随着x的增加逐渐增关键词：热电传输性能n型笼合物框架取代

Thermoelectric transport properties of Zn-doped n-type Ba8Ga16-2xZnxGe30+x clathrates

The single-phase Zn-doped n-type Ba₈Ga_16-2xZn_xGe_30+x clathrates were prepared by melting reaction method combined with spark plasma sintering (SPS). Influences of substituting Zn for Ga on the thermoelectric transport properties of the compounds were investigated. Research results indicate that the electrical conductivity of n-type Ba₈Ga_16-2xZn_xGe_30+x compounds increases gradually with the increasing of Zn substitution fraction x. The Seebeck coefficient decreases gradually with the increasing of x. When Zn replaces Ga entirely, the electrical conductivity of Ba₈Zn₈Ge₃₈ compound drops rapidly and its Seebeck coefficient increases suddenly. Zn substitution fraction x dependence of the thermal conductivity and lattice thermal conductivity are similar in the temperature range from 300 to 1000 K.When x<4, with the increasing of x,lattice thermal conductivity decreases gradually. When x>4, with the increase of x,lattice thermal conductivity increases gradually.In all n_type Ba₈Ga_16-2xZn_xGe_30+x clathrates, Ba₈Ga₈Zn₄Ge₃₄ compound has the greatest ZT value, and its maximal ZT value reaches 085 at about 1000K.