摘 要

BaTiO₃储能薄膜因具有高击穿强度和高储能密度等优点在储能电容器方面得到了广泛的应用。近年来，国内外研究人员发现BaTiO₃储能薄膜的电学性能除了与制备条件有关，还在一定程度上与电极和过渡层材料的质量以及二者之间发生相互扩散作用的程度有关。因此，探索BaTiO₃储能薄膜的制备工艺、选择合适的电极或过渡层材料对BaTiO₃铁电储能薄膜的发展有重要的意义。

本文采用溶胶-凝胶法制备LaNiO₃（LNO）薄膜，研究和探讨了LNO溶液pH、退火温度和退火保温时间对LNO薄膜的物相结构和导电性能的影响。研究结果表明，随着溶液pH的增加，LNO薄膜电阻值总体呈下降趋势；对于同一pH的溶液，样品电阻值随退火温度的升高先降低后增加；随着退火保温时间从2min延长到8min，LNO薄膜电阻值增加0.072kΩ。LNO薄膜底电极的最优制备工艺：溶液pH=6，退火温度为725℃，退火保温时间为2min，制得的LNO薄膜最小电阻值为0.092kΩ，制备的LNO薄膜满足作为0.93BaTiO₃-0.07Bi(Zn_1/2Zr_1/2)O₃（0.93BT-0.07BZZ）储能薄膜底电极的要求。

采用溶胶-凝胶法在LNO底电极上制备了0.93BT-0.07BZZ储能薄膜。研究和探讨了薄膜层数、退火温度对储能薄膜物相结构、介电性能和铁电性能的影响。研究结果表明，介电常数随薄膜厚度的增加而增加，12层时达到最高为448，并且介电常数随频率的变化不大；当样品厚度为10层，退火温度为675℃时，放电储能密度达到最大为14.0 J/cm³，此时充放电储能效率为59.3%，电场强度为1249.8kV/cm，最大剩余极化为3.04μC/cm²。另外，对比了在相同制备条件下，Pt作为底电极时0.93BT-0.07BZZ储能薄膜的性能。当LNO作为底电极时，0.93BT-0.07BZZ储能薄膜的放电储能密度更大，电场强度更高。表明使用LNO底电极材料作为缓冲层来改善0.93BaTiO₃-0.07Bi(Zn_1/2Zr_1/2)O₃储能薄膜的性能是行之有效的且具有实际应用前景。

关键词：储能薄膜；溶胶凝胶；LaNiO₃；0.93BaTiO₃-0.07Bi(Zn_1/2Zr_1/2)O₃

Abstract

BaTiO₃ energy storage film has been widely used in energy storage capacitors because of its high breakdown strength and high energy storage density. In recent years, researchers have found that the electrical properties of BaTiO₃ energy storage films are not only related to the preparation conditions, but also to a certain extent to the quality of the electrode and transition layer materials and the degree of diffusion between them. Therefore, the exploration of the preparation technology of BaTiO₃ energy storage thin films and the selection of suitable electrode or transition layer materials play an important role in the development of BaTiO₃ ferroelectric energy storage thin films.

In this paper, LaNiO₃(LNO) thin films was prepared by sol-gel method. The effects of LNO solution pH, annealing temperature and annealing holding time on the phase structure and electrical conductivity of LNO thin films were studied. The results show that the resistance of LNO film decreases with the increase of solution pH, and decreases at first and then increases with the increase of annealing temperature for the same pH solution. With the prolongation of annealing time from 2min to 8min, the resistance of LNO thin films increases by 0.072kΩ. The optimal preparation process of LNO thin film bottom electrode is as follows: the solution pH=6, annealing temperature is 725℃, the annealing holding time is 2 min, and the minimum resistance of LNO thin film is 0.092kΩ. The prepared LNO thin films meet the requirements of being the bottom electrode of 0.93BaTiO₃-0.07Bi(Zn_1/2Zr_1/2)O₃ (0.93BT-0.07BZZ) energy storage thin films.

In this paper, 0.93BT-0.07BZZ energy storage films were prepared on LNO bottom electrode by sol-gel method. The effects of layer number and annealing temperature on the phase structure, ferroelectric properties and dielectric properties of energy storage thin films were studied and discussed. The results show that the dielectric constant increases with the increase of film thickness, reaches the maximum of 448 at 12 layers, and the dielectric constant changes little with frequency. When the thickness of the sample is 10 layers and the annealing temperature is 675℃, the maximum discharge is 14.0J/cm3, the energy storage efficiency is 59.3%, the electric field intensity is 41V, and the maximum residual polarization is 3.04μC/cm². In addition, we compared the properties of 0.93BT-0.07BZZ energy storage films with Pt as the bottom electrode under the same preparation conditions. By comparison, we know that when LNO is used as the bottom electrode, the discharge and the electric field intensity of 0.93BT-0.07BZZ energy storage film is higher. This shows that using LNO bottom electrode material as buffer layer to improve the performance of 0.93BaTiO₃-0.07Bi(Zn_1/2Zr_1/2)O₃ energy storage film is effective and has a practical application prospect.

Key Words：Energy storage film; Sol-gel; LaNiO₃; 0.93BaTiO₃-0.07Bi(Zn_1/2Zr_1/2)O₃

目录

摘 要 I

Abstract II

第1章 绪论 1

1.1 铁电储能薄膜材料概述 1

1.2 BaTiO₃储能薄膜概述 2

1.3 BaTiO₃储能薄膜制备方法 5

1.4 BaTiO₃储能薄膜底电极概述 6

1.5 本课题研究目的与内容 7

第2章 薄膜制备工艺与性能表征 8

2.1 实验原材料 8

2.2 实验设备 8

2.3 溶胶-凝胶法制备薄膜工艺 9

2.4 薄膜表征手段和测试方法 11

第3章 LNO薄膜性能表征与分析 12

3.1 LNO薄膜电阻测试结果与分析 12

3.2 LNO薄膜XRD测试结果 13

3.3 本章小结 16

第4章 0.93BaTiO₃-0.07Bi(Zn_1/2Zr_1/2)O₃储能薄膜性能表征与分析 17

4.1 LNO底电极上储能薄膜性能表征 17

4.2 Pt底电极与LNO底电极上储能薄膜性能表征结果对比 25

4.3 本章小结 27

第5章 结论 29

致 谢 30

参考文献 31

附录1 33