氢致PZT-5H铁电陶瓷导电性变化

通过实验和第一性原理计算的方法研究了氢致PZT-5H铁电陶瓷导电性变化的规律和机理.随着充H含量的增加,PZT-5H陶瓷的电阻率逐渐降低,当陶瓷中总H的质量分数为11.2×10^-6时电阻率降至1.51×10⁹Ω.cm,介于半导体和绝缘体之间.随着H含量进一步升高,霍尔效应表明PZT-5H陶瓷变成n型半导体.第一性原理计算表明,当进入Pb(Zr_0.5-Ti_0.5)O₃晶格的H质量分数等于临界值(96×10^-6)时,[Pb(Zr_0.5Ti_0.5)O₃]₃₂H系统变成了半导体;随着H含量的升高,态密度图向低能方向平移,[Pb(Zr_0.5Ti_0.5)O₃]_nH系统变成了导体.

Effect of hydrogen on the conductivity of PZT-5H ferroelectric ceramics

The effect of hydrogen on the conductivity of PZT-5H ferroelectric ceramics was investigated by experiment and first-principles calculations.The resistivity of PZT-5H ferroelectric ceramics decreases with the increase of the content of hydrogen doped into the ceramics.When the total hydrogen content is 11.2×10^-6,the resistivity approaches to 1.51×10⁹Ω·cm,which is between the semiconductor and insulator.Further increasing the hydrogen content,the PZT-5H ceramics become an n-type semiconductor from the Hall effect.The results of first-principles calculations show that the [Pb(Zr_0.5Ti_0.5)O₃]₃₂H system,with the hydrogen content of 96×10^-6,becomes a semiconductor.The density of states (DOS) moves toward the lower energy with the increase of hydrogen content.The [Pb(Zr_0.5Ti_0.5)O₃]_nH system becomes a conductor while the hydrogen content is larger than 96×10^-6.