【作者】 李宁；

【导师】 厉英；

【作者基本信息】 东北大学 ， 冶金工程（专业学位）， 2015， 硕士

【摘要】 高温质子导体材料在高温下呈现质子导电,是一种具有广阔应用前景的功能材料,可以应用在燃料电池、传感器、合成氨、核工业等领域。质子导体种类较多,在其性能上各具特点,但是目前尚无一种兼具高质子迁移数及高电导率的质子导体材料,限制了质子导体的进一步应用。因此,本研究根据质子导体的结构与导电性规律,提出制备一种新型的兼具高质子迁移数及高电导率的质子导体材料 CaH1-xScxO₃-δ。研究制备不同掺杂量的CaHf_1-xSc_xO_3-δ材料,探索其制备工艺,研究其物相组成、电导率、电导激活能、质子迁移数等性能。另外制备的CaZr_0.9In_0.1O_3-δ,CaZr_0.9Sc_0.1O_3-δ,Ba₃Ca_1.18Nb₍1.82_O9-δ,SrCe0.9Y0.103-δ质子导体材料,研究对比CaHf_1-xSc_xO_3-δ与这些现有材料的性能特点。为新型质子导体的开发提供了理论依据与实验探索,为新型质子导体的应用提供了实验数据,具有重要的科学意义与现实价值。本研究得到了如下成果:（1）研究提出了研制一种新型的质子导体材料CaHf_1-xSc_xO_3-δ,采用固相合成法制备了 CaHf_1-xSc_xO_3-δ（x=0,x=0.1,x=0.2,x=0.3）,XRD 分析结果表明,1100℃锻烧 10h可以合成CaHf_1-xSc_xO_3-δ材料。（2）电化学阻抗谱分析结果表明,在Ar-H₂混合气氛中400～900℃,CaHf_1-xSc_xO_3-δ样品的电导率均随着温度的提高而增大。Sc的掺杂可以显著提高CaHfO₃基材料的电导率,当Sc掺杂量x=0.1时,CaHf_1-xSc_xO_3-δ样品的电导率达到最大为1.88×10-3S/cm,Sc掺杂量x=0.1,为CaHf_1-xSc_xO_3-δ材料的最佳掺杂量。（3）在质子导体的制备过程中,增大CaHf_1-xSc_xO_3-δ材料的晶粒尺寸,减少晶界面积,有利于提高CaHf_1-xSc_xO_3-δ材料的电导率。（4）电导率的Arrhenius线性拟合结果表明,得出在本实验条件下CaHf_1-xSc_xO_3-δ（x=0、0.1、0.2、0.3）的电导激活能Ea 分别为:0.66eV、0.35eV、0.37eV、0.34eV。（5）电导率分析结果表明,在 CaHf_0.9Sc_0.1O_3-δ、CaZr_0.9Sc_0.1O_3-δ、Ba₃Ca_1.18Nb₍1.82_O9-δ、SrCe0.9Y_0.1O_3-δ样品中,CaHf_0.9Sc_0.1O_3-δ、CaZr_0.9Sc_0.1O_3-δ样品在 400～900℃整个温度段,电导率均较高,CaHf_0.9Sc_0.1O_3-δ的电导率高于CaZr_0.9Sc_0.1O_3-δ,在550～900℃的范围内CaHf_0.9Sc_0.1O_3-δ的电导率最高,当温度低于550℃时,CaHf_0.9Sc_0.1O_3-δ电导率仅略低于Ba₃Ca_1.18Nb₍1.82_O9-δ的电导率,因此,CaHf_0.9Sc_0.1O_3-δ为本研究制备的最佳质子导体材料。（6）质子迁移数分析结果表明,CaZr_0.9In_0.1O_3-δ在500-750℃之间质子迁移数t>0.9,几乎为纯质子导体材料。CaHf_0.9Sc_0.1O_3-δ在500-850℃之间t>0.9,几乎为纯质子导体材料。研究开发的CaHf_0.9Sc_0.1O_3-δ材料的工作温度范围较大,质子导电性能明显优于CaZr_0.9In_0.1O_3-δ 材料。更多还原

【Abstract】 High temperature proton conductor material exhibits proton conductivity at high temperatures.It is a kind of functional material with wide application prospect,which can be used in fuel cell,sensor,synthetic ammonia,nuclear industry and so on.There are many kinds of proton conductor.Its performance has its own characteristics.At present,there is no proton conductor material with high proton transfer number and high electric conductivity,which limits the further application of proton conductors.Therefore,according to the structure and electrical conductivity of proton conductors,a novel proton conductor material CaHf_1-xSc_xO_3-δ,which has high proton transfer number and high conductivity,is proposed.This paper was prepared different doping amount of CaHf_1-xSc_xO_3-δ,exploring to study the phase composition,conductivity,conductivity activation energy,proton transport number and other properties.CaZr_0.9ln_0.1O_3-δ,CaZr_0.9Sc_0.1O_3-δ,Ba₃Ca_1.18Nb₍1.82_O9-δ,SrCe0.9Y0.1O₃ were prepared,and the properties of these materials were compared.The development of the new type of proton conductor provides the theoretical basis and the experimental exploration.It provides experimental data for the application of the new proton conductor.It has important scientific significance and practical value.The main achievements of this work are following:1.This paper proposed to develop a new proton conductor material,CaHf_1-xSc_xO_3-δ.It was prepared by solid-phase synthesis,Doping content of CaHf_1-xSc_xO_3-δ.s:x=0,x=0.1,x=0.2,x=0.3.XRD analysis showed that the calcination conditions were 1100℃,10h.2.The results of electrochemical impedance spectroscopy show that the electrical conductivity,CaHf_1-xSc_xO_3-δ,increases with the increase of temperature in Ar-H₂ mixed atmosphere at 400-900 ℃.Sc doping can significantly improve the electrical conductivity of CaHfO₃ based materials.When Sc is doped,x=0.1,the electrical conductivity is the largest,reaching up to 1.88x10-3S/cm.x=0.1 is the best.3.In the process of the preparation of proton conductor,the grain size can be increased and the grain boundary area can be reduced,which is beneficial to improve the electrical conductivity of CaHf_0.9Sc_0.1O_3-δ.4.Arrhenius equation were obtained through the data fitting and calculation.The conductivity activation energy was about 0.66eV（x=0）,0.35eV（x=0.1）,0.37eV（x=0.2）,0.34eV（x=0.3）.5.Electrical conductivity analysis results show that CaHf_0.9Sc_0.1O_3-δ and CaZr_0.9Sc_0.1O_3-δhave the higher conductivity at 400-900℃.And CaHf_0.9Sc_0.1O_3-δis better than CaZr_0.9Sc_0.1O_3-δ.CaHf_0.9Sc_0.1O_3-δ is the best at 550-900℃.CaHf_0.9Sc_0.1O_3-δ is slightly lower than Ba₃Ca_1.18Nb₍1.82_O9-δ.So the best proton conductor material for the study is CaHf_0.9Sc_0.1O_3-δ.6.The results about the protonic transport number show thatCaZr_0.9In_0.1O_3-δ is almost a pure proton conductor material at 500-750℃,CaHf_0.9Sc_0.1O_3-δ is almost a pure proton conductor material at 500-850 ℃.Because the protonic transport number is more than 0.9.And CaHf_0.9Sc_0.1O_3-δ is better than CaZr_0.9In_0.1O_3-δ about the Protonic conductivity.更多还原