摘要
用固态反应法制备了YBa2Cu3-xCoxO7-δ(x=0.0,0.1,0.2,0.5)样品,研究了Co掺杂对YBa2Cu3O7-δ高温区的电阻率和塞贝克系数的影响。随着Co含量的增加,样品的电阻率和塞贝克系数逐渐增大,从金属性导电转变为p型半导体导电。x=0.2和0.5样品的电导活化能在500K处发生突变,高温区的活化能大于低温区的活化能。通过塞贝克系数与温度的关系,计算出x=0.2和0.5样品的费米能级分别为0.02和0.12 eV。当温度高于650-700K时,氧脱附显著影响样品的电输运性质,导致电阻率和塞贝克系数随温度增加而增大。
YBa2Cu3 -x Cox O7-δ （x = 0.0, 0. 1,0.2, 0.5 ） samples were prepared by solid- state reaction method. Effect of Co doping on electrical resistivity and Seebeck coefficient of YBa2Cu3O7 -δ at high temperature were investigated. Electrical resistivity and Seebeek coefficients of the samples increase with the increasing Co content and transport behavior transforms from metallic conduction to p - type semi - conducting one. A change of activation energy was found at 500K for x = 0.2 and 0. 5 samples and the value at high temperature is larger than that at low temperature. Fermi energy calculated from the variation of Seebeck coefficients with temperature is 0.02 and 0.12eV for x = 0.2 and 0.5 sample respectively. Above 650 - 700K, oxygen desorption from samples influences the transport behavior obviously and electri- cal resistivity and Seebeck coefficients increase with the increasing temperature.
出处
《低温与超导》
CAS
CSCD
北大核心
2007年第1期48-50,92,共4页
Cryogenics and Superconductivity
