發(fā)布時(shí)間：2018-04-13 13:43

  本文選題：鈦酸鉛 + 鐵酸鉍　； 參考：《北京科技大學(xué)》2017年博士論文

【摘要】：鐵電薄膜作為一類重要的多功能基礎(chǔ)材料而倍受關(guān)注,在電子器件、信息技術(shù)、儲(chǔ)能裝置中有廣泛的應(yīng)用前景。鈦酸鉛和鐵酸鉍都是集鐵電和壓電等多種優(yōu)異性能于一身的典型鈣鈦礦型材料,通過化學(xué)替代和應(yīng)力工程的調(diào)控等途徑可以有效對薄膜的結(jié)構(gòu)和性能進(jìn)行改良。本文以鈦酸鉛和鐵酸鉍為出發(fā)點(diǎn),通過A位、B位不同元素替代和各向同性應(yīng)力、基底雙軸應(yīng)力引入,采用不同的化學(xué)法和物理法制備出了一系列性能優(yōu)異的鐵電薄膜。系統(tǒng)的研究了化學(xué)替代和應(yīng)力調(diào)控對鈦酸鉛基和鐵酸鉍基鐵電薄膜的晶體結(jié)構(gòu)、電子結(jié)構(gòu)、晶格動(dòng)力學(xué)、鐵電性、鐵磁性及鐵電相關(guān)等性能的影響。首先研究不同元素取代對PbTiO3-BiMeO3體系的合成以及鐵電等性能的影響。通過對PbTiO3-Bi(Zn1/2Zr1/2)O3, PbTiO3-Bi(Mg1/2Zr1/2)O3,PbTiO3-Bi(Mg1/2Ti1/2)O3三大薄膜體系的探索,不僅得到鐵電性好、耐疲勞、溫度穩(wěn)定性好的鐵電薄膜材料,還直接從實(shí)驗(yàn)的角度揭示Ti、Zn離子在PbTiO3-BiMeO3體系中的鐵電活性分別大于Zr、Mg離子。同時(shí)在鐵電體中首次通過高分辨X射線同步輻射直觀揭示鐵電極化復(fù)蘇歸因于疇結(jié)構(gòu)的變化。通過“相界面”應(yīng)力的引入,制備了大軸比的超四方PbTiO3復(fù)合外延薄膜。報(bào)道了目前鐵電體中的最大剩余極化(236.3μC/cm2)。同時(shí)相轉(zhuǎn)變溫度從塊體的490℃提高到了725℃。第一性原理計(jì)算、透射電鏡、X射線吸收譜等手段觀察和解釋了“相界面”應(yīng)力的作用和巨大極化的原因。第一次采用脈沖激光法(PLD)在A1203基底上成功制備了大軸比BiFe03的外延薄膜。通過變溫同步輻射的測試,得到了薄膜的低膨脹特性。通過第一性原理計(jì)算、變溫磁性等表征解釋了低膨脹性的機(jī)理是鐵電性、磁相轉(zhuǎn)變、基底應(yīng)力共同耦合的作用。采用Co和Ni對BiFe03基薄膜的取代,得到優(yōu)異鐵電性、巨大鐵電阻變、可翻轉(zhuǎn)的鐵電光伏的多功能鐵電薄膜。同時(shí)通過界面的調(diào)控,實(shí)現(xiàn)了鐵電光伏信號(hào)三倍多的提高。
[Abstract]:Ferroelectric thin films have attracted much attention as a kind of multifunctional important basic material and information technology in the electronic device, the storage device has a wide application prospect. Lead titanate and bismuth ferrite are typical Perovskite Ferroelectric and piezoelectric materials in a variety of excellent performance in a body, and alternative stress engineering control approaches can effectively on the structure and properties of thin films were modified by chemical. The lead titanate and bismuth ferrite as the starting point, through A, B different element substitution and isotropic stress, basal biaxial stress introduced by different chemical method and physical method to prepare a series of performance excellent ferroelectric thin films was studied. The chemical substitution and stress control of crystal structure of lead titanate and bismuth based ferroelectric thin film electronic structure, lattice dynamics, ferroelectric, ferromagnetic and ferroelectric effect related properties. First of all. The different elements substitution effect on the PbTiO3-BiMeO3 system of the synthesis and properties of ferroelectric. Based on PbTiO3-Bi (Zn1/2Zr1/2) O3, PbTiO3-Bi (Mg1/2Zr1/2) O3, PbTiO3-Bi (Mg1/2Ti1/2) to explore the O3 three thin film system, not only have good ferroelectric properties of ferroelectric thin film materials, fatigue resistance, good temperature stability, but also reveal directly from Ti the angle of the experiment, the activity of Zn ferroelectric ions in PbTiO3-BiMeO3 system were greater than Zr, Mg ion. At the same time for the first time in ferroelectrics by high resolution synchrotron radiation X ray directly reveal the ferroelectric polarization recovery is attributed to the domain structure changes. According to the introduction of "interface" stress, super tetragonal PbTiO3 composite epitaxial thin shaft the ratio was prepared. The ferroelectric in maximum residual polarization reports (236.3 C/cm2). At the same time, the phase transition temperature increased from block 490 C to 725 C. First principle calculation, transmission electron microscope, X ray The absorption spectrum is used to observe and explain the reason of the effect of interfacial stress and great polarization. First by pulsed laser method (PLD) was successfully prepared large axial ratio of BiFe03 epitaxial thin films on A1203 substrates. The temperature dependent synchrotron radiation test, obtained the low expansion properties of thin films by. The first principle calculation, and explains the low temperature magnetic characterization of the expansion mechanism is ferroelectric, magnetic phase transition, the substrate stress coupling effect. The Co and Ni of BiFe03 films obtained excellent substitution, ferroelectricity, huge iron resistance, multifunctional ferroelectric thin film ferroelectric photovoltaic flip. At the same time through the interface control, realizes signal ferroelectric photovoltaic three times more improved.

【學(xué)位授予單位】：北京科技大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2017
【分類號(hào)】：TB383.2

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 ;Novel thermal expansion of lead titanate[J];Rare Metals;2003年04期

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本文編號(hào)：1744792