【摘要】：鉍層狀結(jié)構(gòu)氧化物是一類由類螢石結(jié)構(gòu)的(Bi202)2+和類鈣鈦礦結(jié)構(gòu)的[Am-1BmO3m+1]2-(其中m為層數(shù))單元沿c方向周期性排列的層狀材料,由于其在室溫以上同時(shí)具有鐵電性和鐵磁性,因而近年來備受關(guān)注。在鉍層狀結(jié)構(gòu)氧化物中,Ti/Fe離子不均勻地占據(jù)類鈣鈦礦B位八面體中心,并與周圍氧離子間形成強(qiáng)的相互作用；這種非中心對(duì)稱結(jié)構(gòu)以其離子間強(qiáng)的相互作用共同決定了它們特殊的鐵電性和鐵磁性,從而為人們研究和探索新型多鐵材料提供了一條新的途徑,并有望被應(yīng)用到信息存儲(chǔ)、傳感器,甚至其它量子器件中。研究表明,鉍層狀結(jié)構(gòu)氧化物的多鐵性能與其周期長(zhǎng)短有關(guān)。短周期的氧化物(如4層的Bi5FeTi3O1 5層的Bi6Fe2Ti3O18和6層的Bi7Fe3Ti3O21)在室溫下一般表現(xiàn)出順磁性,而長(zhǎng)周期的氧化物(如7層的BigFe4Ti3O24和8層的Bi9Fe5Ti3O27)在室溫下通常表現(xiàn)為反鐵磁性,有時(shí)候甚至?xí)霈F(xiàn)弱的鐵磁性。長(zhǎng)周期氧化物這種獨(dú)特的鐵磁和反鐵磁的共存現(xiàn)象以及可能存在的相互作用,將會(huì)使長(zhǎng)周期氧化物在一定溫度下呈現(xiàn)玻璃態(tài),甚至可能引發(fā)交換偏置現(xiàn)象,成為一種新的交換偏置材料。本論文以進(jìn)一步研究和探索鉍層狀結(jié)構(gòu)氧化物的新穎多鐵性能和機(jī)理為目標(biāo),主要進(jìn)行以下研究,包括：1)Co/Y共摻雜Bi7Fe3Ti3O21材料的制備及性能關(guān)系研究;2)長(zhǎng)周期Bi10Fe6Ti3O30氧化物的制備、結(jié)構(gòu)和變溫多鐵性能關(guān)系研究,探討可能的交換偏置現(xiàn)象；3)Co摻雜Bi10Fe6Ti3O30的結(jié)構(gòu)性能研究及性能影響關(guān)系。論文主要結(jié)果如下：第一章：分別介紹了鐵電材料和磁性材料,給出了磁性材料中各種磁性的分類；并介紹了同時(shí)具有鐵電性能和磁學(xué)性能的多鐵材料的特性及應(yīng)用領(lǐng)域。本論文的工作以在室溫下同時(shí)具有鐵電性和鐵磁性的單相奧里維里斯(Aurivillius)結(jié)構(gòu)鉍層狀氧化物為關(guān)注焦點(diǎn),分析了鉍層狀氧化物的結(jié)構(gòu)特點(diǎn)和性能關(guān)系,確立了本論文的研究方向,即：優(yōu)化摻雜Aurivillius結(jié)構(gòu)材料的制備并探討摻雜含量對(duì)其鐵電和鐵磁等多鐵行為的改性研究；長(zhǎng)周期鉍層狀氧化物的新型交換偏置效應(yīng)及其與摻雜元素間的關(guān)系。第二章：采用改進(jìn)的燃燒法制備奧里維里斯(Aurivillius)相鉍層狀氧化物。本工作改進(jìn)了傳統(tǒng)的以固相反應(yīng)法制備鉍層狀氧化物的工藝,采用改進(jìn)的燃燒法制備氧化物粉體,并進(jìn)一步通過馬弗爐燒結(jié)或者熱壓燒結(jié)得到陶瓷樣品。由于Aurivillius相鉍層狀氧化物的結(jié)構(gòu)比較復(fù)雜,穩(wěn)定性較低,制備條件窗口較小,因此本工作選擇了短周期的Bi7Ti3Fe3O21進(jìn)行探索性制備；并進(jìn)而探討Co、Y共摻雜時(shí)釔的摻雜量的改變對(duì)材料的多鐵性能的影響關(guān)系。實(shí)驗(yàn)結(jié)果證明,鈷加入之后,會(huì)與鐵通過周圍的氧離子形成耦合,從而大幅增強(qiáng)了材料的鐵磁性能。另外,具有4d空軌道且半徑更小的釔的加入也同時(shí)提高了材料的鐵電性能和鐵磁性能。磁失重測(cè)試結(jié)果表明,在一定量的Y摻雜范圍內(nèi),材料的多鐵行為主要來自于本征性能。第三章：介紹了一種通常產(chǎn)生在兩種磁性材料界面處的耦合相互作用,即交換偏置效應(yīng),并分析了交換偏置效應(yīng)與材料體系組成和結(jié)構(gòu)間的相互關(guān)系,提出了發(fā)展新型單相長(zhǎng)周期交換偏置材料的新構(gòu)想。交換偏置效應(yīng)的發(fā)現(xiàn)對(duì)于自旋電子學(xué)的基礎(chǔ)研究和應(yīng)用發(fā)展起到了非常重要的作用。交換偏置現(xiàn)象通常出現(xiàn)在：1)同時(shí)包含有鐵磁和反鐵磁組分的體系中；2)目前也拓展到一些多鐵的異質(zhì)結(jié)體系。在這類多鐵異質(zhì)結(jié)體系中,由于存在磁電耦合效應(yīng),因此其交換偏置效應(yīng)不僅可以通過磁場(chǎng)來調(diào)控,還可以通過電場(chǎng)來調(diào)控,因而具有更大的調(diào)控自由度；3)空穴摻雜型的錳氧化物和鈷氧化物等,由于材料中存在著結(jié)構(gòu)相分離和電子相分離現(xiàn)象,因此往往形成幾種不同的相共存體系(包括鐵磁和反鐵磁相的共存),這種內(nèi)在相分離產(chǎn)生的交換偏置效應(yīng)為我們探索單相的交換偏置材料提供了可能性。由于影響交換偏置場(chǎng)的因素非常復(fù)雜,因此現(xiàn)有的理論模型均不能很清晰、全面的解釋實(shí)驗(yàn)中觀測(cè)到現(xiàn)象。第四章：發(fā)現(xiàn)了一種具有顯著交換偏置效應(yīng)的單相長(zhǎng)周期鉍層狀氧化物多鐵材料Bi10Fe6Ti3O30。在通過掃描透射電子顯微鏡的高角環(huán)形暗場(chǎng)相(STEM-HAADF)等實(shí)驗(yàn)手段直接觀測(cè)到了這種長(zhǎng)周期的氧化物中磁性鐵離子的不均勻分布現(xiàn)象,證實(shí)了短周期磁有序性的存在,即團(tuán)簇玻璃態(tài)和自旋傾斜反鐵磁。研究結(jié)果表明反鐵磁自旋和團(tuán)簇玻璃態(tài)之間的相互作用受到溫度的影響,并在合適的溫度下會(huì)出現(xiàn)交換偏置現(xiàn)象。該樣品的交換偏置場(chǎng)遠(yuǎn)高于相分離體系和多鐵異質(zhì)結(jié)體系的一些材料的交換偏置場(chǎng)。這種具有顯著的交換偏置效應(yīng)的新的單相層狀多鐵材料的發(fā)現(xiàn),不僅有利于基礎(chǔ)物理研究的發(fā)展,更是推動(dòng)了交換偏置器件應(yīng)用的步伐。第五章：通過改性手段,對(duì)單相長(zhǎng)周期鉍層狀氧化物多鐵材料Bi10Fe6Ti3O30進(jìn)行B位鈷摻雜的嘗試制備以及多鐵性和相關(guān)性能的研究。實(shí)驗(yàn)結(jié)果表明材料的磁性受摻雜Co的含量影響很大。當(dāng)樣品中只含有Fe元素時(shí),樣品隨著溫度的不同通常表現(xiàn)出順磁性或反鐵磁性。而隨著Co含量的增加,樣品體現(xiàn)出由順磁向鐵磁性能演變。這主要是由于在長(zhǎng)周期結(jié)構(gòu)的氧化物中,類鈣鈦礦單元中Fe和Co位置的選擇更多,可能會(huì)出現(xiàn)不同的結(jié)合狀態(tài),因此比較容易捕捉到磁性的演變過程。對(duì)于這類材料,它們獨(dú)特的非中心對(duì)稱結(jié)構(gòu)和氧八面體中心Ti、Fe、Co的不均勻分布,以及與周圍氧離子之間的強(qiáng)烈的相互作用,是其奇特的鐵電性能和鐵磁性能的主要來源。第六章：全文內(nèi)容的總結(jié)以及對(duì)未來工作的展望。
[Abstract]:Bismuth layered oxides are a class of fluorite-like (Bi202)2+ and perovskite-like (Am-1BmO3m+1]2-(in which m is the number of layers) layered materials with periodic alignment along the C direction. Ti/Fe ions are not found in bismuth layered oxides due to their ferroelectric and ferromagnetic properties above room temperature. The perovskite-like B-site octahedron occupies the center of perovskite-like octahedron evenly and forms a strong interaction with the surrounding oxygen ions. This kind of non-central symmetric structure determines their special ferroelectricity and ferromagnetism by the strong interaction between ions, which provides a new way for people to study and explore new Polyferrous materials and is expected to be used. Studies have shown that the polyferric properties of bismuth layered oxides depend on the period length. Short-period oxides (such as 4-layer Bi5FeTi3O1 5-layer Bi6Fe2Ti3O18 and 6-layer Bi7Fe3Ti3O1) generally exhibit paramagnetism at room temperature, while long-period oxides (such as 7-layer BigFe) exhibit paramagnetism. 4Ti3O2 4 and 8-layer Bi9Fe5Ti3O2 7) usually exhibit antiferromagnetism at room temperature, sometimes even weak ferromagnetism. Long-period oxides, a unique coexistence of ferromagnetism and antiferromagnetism, and possible interactions, will make long-period oxides present glass state at a certain temperature and may even cause exchange bias. In order to further study and explore the novel multi-ferrous properties and mechanism of bismuth layered oxides, the following studies have been carried out: 1) preparation of Co/Y co-doped Bi_7Fe_3Ti_3O_2_1 and its performance relationship; 2) preparation, structure and properties of long-period Bi_ 10Fe_ 6Ti_ 3O_ 30 oxide. The main results of this paper are as follows: Chapter 1: Ferroelectric and magnetic materials are introduced separately, and the classification of various magnetism in magnetic materials is given; and the ferroelectric properties of Bi10Fe6Ti3O30 doped with Co are also introduced. In this paper, the structure and properties of bismuth layered oxides with ferroelectric and ferromagnetic properties at room temperature are analyzed, and the research direction of this paper is established. The preparation of chemically doped Aurivillius structural materials and the modification of their ferroelectric and ferromagnetic properties by doping content were investigated; the new exchange bias effect of long-period bismuth layered oxides and its relationship with doping elements were investigated. The traditional method of preparing bismuth layered oxides by solid-state reaction was improved. Oxide powders were prepared by improved combustion method, and ceramic samples were obtained by muffle furnace sintering or hot-pressing sintering. In this work, short period Bi7Ti3Fe3O2 1 was selected for exploratory preparation, and the effect of yttrium doping on the multi-ferromagnetic properties of the materials was discussed. The experimental results show that the ferromagnetic properties of the materials are greatly enhanced by the coupling of cobalt with iron through the surrounding oxygen ions. The addition of Yttrium with smaller radius and d-empty orbits also improves the ferroelectric and ferromagnetic properties of the materials. The results of magnetic weightlessness measurements show that in a certain range of Y-doping, the multi-ferroelectric behavior of the materials mainly comes from the intrinsic properties. Chapter 3: A coupling interaction between two kinds of magnetic materials is introduced. The exchange bias effect and the relationship between the exchange bias effect and the composition and structure of the material system are analyzed. A new idea for developing new single-phase long-period exchange bias materials is proposed. It appears as follows: 1) in systems containing both ferromagnetic and antiferromagnetic components; 2) at present, it is also extended to some multi-ferromagnetic heterojunction systems. 3) Hole-doped manganese oxides and cobalt oxides, due to the existence of structural phase separation and electronic phase separation, often form several different phase coexistence systems (including the coexistence of ferromagnetic and antiferromagnetic phases), the exchange bias effect produced by this internal phase separation for us to explore the exchange of single phase. Biased materials provide possibilities. Due to the complexity of the factors affecting the exchange bias field, the existing theoretical models are not clear enough to fully explain the phenomena observed in the experiments. The inhomogeneous distribution of magnetic iron ions in such long period oxides has been observed directly by means of high angle ring dark field phase (STEM-HAADF) and other experimental means of TEM, which confirms the existence of short period magnetic ordering, i.e. cluster glass state and spin-tilted antiferromagnetism. The exchange bias field of the sample is much higher than that of some materials in the phase separation system and the multiferrous heterojunction system. The discovery of a new single-phase layered multiferrous material with significant exchange bias effect is not only advantageous. The development of basic physics has promoted the application of exchange bias devices. Chapter 5: Trial preparation of B-site cobalt-doped Bi10Fe6Ti3O30, a single-phase long-period bismuth layered oxide polyferric material, by means of modification, and the study of its polyferricity and related properties have been carried out. When only Fe is present in the samples, the samples usually exhibit paramagnetism or antiferromagnetism at different temperatures. With the increase of Co content, the samples exhibit paramagnetism to ferromagnetism. This is mainly due to the fact that the positions of Fe and CO in perovskite-like units are more selective in oxides with long-period structure. For these materials, their unique noncentrosymmetric structure and the inhomogeneous distribution of Ti, Fe, Co at the center of the oxygen octahedron, as well as the strong interaction with the surrounding oxygen ions, are the main sources of their unique ferroelectric and ferromagnetic properties. Chapter: summary of the full text and prospects for future work.
【學(xué)位授予單位】：中國(guó)科學(xué)技術(shù)大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2015
【分類號(hào)】：O611

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 繆明明，，廖代正，姜宗慧，王耕霖;具有強(qiáng)反鐵磁相互作用的線性三核銅（Ⅱ）配合物的合成與磁性[J];高等學(xué)校化學(xué)學(xué)報(bào);1995年02期

2 黃海林;丁林杰;孫照宇;;鐵磁—反鐵磁—反鐵磁三聚自旋鏈的磁化特性[J];武漢工業(yè)學(xué)院學(xué)報(bào);2013年04期

3 張勇,韓梅,魏國(guó)柱;層內(nèi)鐵磁-層間反鐵磁雙層系統(tǒng)零溫性質(zhì)[J];南京化工大學(xué)學(xué)報(bào)(自然科學(xué)版);2001年04期

4 王茂華;許小勇;胡經(jīng)國(guó);;鐵磁/反鐵磁雙層膜中的磁化性質(zhì)與界面微結(jié)構(gòu)[J];功能材料與器件學(xué)報(bào);2009年06期

5 王奇,吳中,王利強(qiáng);反鐵磁晶體表面上的非線性電磁波[J];中國(guó)科學(xué)(A輯);1998年12期

6 王治國(guó),任煜;交錯(cuò)相互作用反鐵磁鏈的臨界區(qū)域[J];周口師范高等�？茖W(xué)校學(xué)報(bào);1999年02期

7 戴守愚,黃錫成,G.Filoti;鈷吸附對(duì)α-Fe_2O_3Morin相變的影響[J];科學(xué)通報(bào);1985年03期

8 代波;蔡健旺;賴武彥;;界面摻雜FeMn對(duì)CoFe/CrPt交換偏置體系的影響[J];功能材料;2007年05期

9 代波;雷勇;邵曉萍;倪經(jīng);;Mn成分對(duì)CoFe/Pt_(50)(Cr_(100-x)Mn_x)_(50)體系交換偏置的影響[J];功能材料;2010年01期

10 潘旋;周廣宏;朱雨富;韋軍;;基于NiMn的鐵磁/反鐵磁系統(tǒng)中交換偏置研究進(jìn)展[J];功能材料;2013年18期

相關(guān)會(huì)議論文 前6條

1 周仕明;;鐵磁/反鐵磁交換偏置中一些問題的研究[A];第四屆全國(guó)磁性薄膜與納米磁學(xué)會(huì)議論文集[C];2004年

2 宋濤;朱士群;郝翔;;反鐵磁開鏈兩端量子態(tài)信息的交換[A];第十七屆十三�。ㄊ校┕鈱W(xué)學(xué)術(shù)年會(huì)暨“五省一市光學(xué)聯(lián)合年會(huì)”論文集[C];2008年

3 呂樹臣;;磁性—非磁性超晶格與反鐵磁—非磁超晶格的反射和透射[A];面向21世紀(jì)的科技進(jìn)步與社會(huì)經(jīng)濟(jì)發(fā)展（上冊(cè)）[C];1999年

4 王修光;劉忠義;楊恩翠;趙小軍;;一個(gè)可逆的藍(lán)色變磁骨架到粉色反鐵磁有序?qū)拥膯尉У絾尉У霓D(zhuǎn)變[A];第十二屆固態(tài)化學(xué)與無機(jī)合成學(xué)術(shù)會(huì)議論文摘要集[C];2012年

5 林勤;陸果;劉尊孝;張玉芬;;(GdSm)_(1.85)Ce_(0.15)CuO_4的超導(dǎo)和反鐵磁有序[A];首屆中國(guó)功能材料及其應(yīng)用學(xué)術(shù)會(huì)議論文集[C];1992年

6 黃一枝;吳立明;;RE_4O_4Se_3(RE=Gd、Tb、Dy)中幾何失措的抑制與長(zhǎng)程反鐵磁有序[A];中國(guó)化學(xué)會(huì)第28屆學(xué)術(shù)年會(huì)第8分會(huì)場(chǎng)摘要集[C];2012年

相關(guān)博士學(xué)位論文 前10條

1 黃妍;單相長(zhǎng)周期鉍層狀多鐵材料的交換偏置效應(yīng)[D];中國(guó)科學(xué)技術(shù)大學(xué);2015年

2 白宇浩;鐵磁/反鐵磁體系中交換偏置的角度依賴關(guān)系及其階躍現(xiàn)象[D];內(nèi)蒙古大學(xué);2010年

3 周勝;反鐵磁/電介質(zhì)體系磁光學(xué)非線性研究[D];哈爾濱理工大學(xué);2010年

4 劉洋;鐵磁—反鐵磁薄膜中的耦合和輸運(yùn)行為研究[D];北京科技大學(xué);2015年

5 白晶;反鐵磁體系三階非線性效應(yīng)理論研究[D];哈爾濱理工大學(xué);2011年

6 何驚華;鐵氧體基復(fù)合系統(tǒng)磁性及交換偏置[D];華中科技大學(xué);2009年

7 詹曉芝;無序系統(tǒng)中交換偏置效應(yīng)的研究[D];華南理工大學(xué);2014年

8 劉奎立;過渡金屬摻雜氧化物的磁性和交換偏置效應(yīng)研究[D];華中科技大學(xué);2010年

9 徐建清;磁性多層薄膜中電流誘導(dǎo)的磁化翻轉(zhuǎn)與振蕩[D];南京大學(xué);2012年

10 高鐵仁;垂直磁記錄介質(zhì)的制備及物性研究[D];復(fù)旦大學(xué);2006年

相關(guān)碩士學(xué)位論文 前10條

1 張華;反鐵磁耦合三層膜體系磁化反轉(zhuǎn)過程的微磁學(xué)模擬[D];四川師范大學(xué);2015年

2 任澤國(guó);鉆石鏈上反鐵磁Spin-1/2 Ising模型的精確解[D];曲阜師范大學(xué);2015年

3 楚海港;具有合成反鐵磁結(jié)構(gòu)的L1_0FePt基垂直交換耦合復(fù)合薄膜的研究[D];復(fù)旦大學(xué);2014年

4 吳國(guó)貞;輔助鐵磁層對(duì)鐵磁/反鐵磁雙層膜中交換偏置的影響[D];東北大學(xué);2013年

5 曹永哲;磁場(chǎng)中A類反鐵磁模型的熱糾纏[D];延邊大學(xué);2007年

6 范志超;垂直外場(chǎng)中反鐵磁三明治結(jié)構(gòu)的二次諧波效應(yīng)[D];哈爾濱師范大學(xué);2013年

7 高欣華;反鐵磁三明治結(jié)構(gòu)的二次諧波生成[D];哈爾濱師范大學(xué);2009年

8 楊蘇揚(yáng);鐵磁/反鐵磁圖紋結(jié)構(gòu)的制備及交換偏置效應(yīng)的研究[D];吉林師范大學(xué);2012年

9 樊維佳;鐵磁/反鐵磁雙層膜中交換偏置效應(yīng)的研究[D];復(fù)旦大學(xué);2009年

10 張娟;帶反鐵磁層復(fù)合結(jié)構(gòu)絲的制備和磁性研究[D];華東師范大學(xué);2011年

本文編號(hào)：2217323