Pb1-3x/2Eux(Zr0.52,Ti0.48)O3纳米粉的溶胶-凝胶合成

采用改进的溶胶－凝胶法制备出稀土铕掺杂PZT（PEZT）的纳米粉，粒径约为20nm.由XRD分析了Eu的掺入对PZT微观结构的影响，确定了Eu的最佳掺入量≤7％，分析了Eu在PZT中的占位情况。     

退火工艺对溶胶凝胶Pb(Zr0.52Ti0.48)O3薄膜残余应力的影响

使用溶胶凝胶法制备了Pb(Zr0.52Ti0.48)O3 铁电薄膜,分别利用原子力显微镜、X射线衍射及面探扫描技术分析了薄膜的组织结构,并运用掠入射X射线衍射法研究了不同工艺条件下制备的薄膜的残余应力.研究表明溶胶凝胶薄膜在600℃退火30min后完全晶化,组织结构均匀.不同工艺下制备的薄膜均受残余拉应力,随着退火温度及退火时间的延长,薄膜中的残余应力逐渐增大,而随着薄膜厚度的增加,残余应力先增大然后减小.     

溶胶-凝胶工艺合成Ti(C,N)超细粉末

以TiO（OH）₂溶胶和炭黑为主原料,采用溶胶-凝胶工艺。经N₂气氛下碳热还原合成了Ti（C,N）超细粉末．分析了合成过程的热力学,探讨了原料配比、合成温度、保温时间和氮气流量等工艺参数对Ti（C,N）组成和性能的影响．通过控制工艺条件,可以得到x值为0．2～0．7,粒径＜100nm的Ti（C_1-x,N_x）超细粉末.     

改性溶胶-凝胶法制备ZrO2纳米粉及其团聚控制

对溶胶-凝胶法进行改性，使凝胶聚沉为沉淀物，进而可以成功地合成ZrO2(9mol％Y2O3)纳米粉体。采用热重-差热(TG-DTA)分析、粒度分布分析(CILAS)、透射电子显微镜(TEM)和X射线衍射(XRD)测试对粉料制备工艺过程进行了研究。结果表明，改性的溶胶-凝胶法，在聚沉前加入分子量大小不同的表活剂．聚沉后采用无水乙醇超声分散，可以有效地消除团聚现象。沉淀产物在450％以下可以完全分解为ZrO2(Y203)粉体，600％煅烧颗粒粒度为14nm。     

溶胶-凝胶法制备纳米Y2O3粉体

为了改善Y2O3粉体的分散性,提高其烧结活性,试验以三乙醇胺和氨水为凝胶剂,利用溶胶-凝胶方法合成了纳米级Y2O3粉体,采用差热/热重、X射线衍射、透射电镜研究了前驱体的组成、前驱体在不同的煅烧温度下的物相变化以及煅烧粉体的分散性.结果表明,前驱体的组成为Y2(OH)5.14(NO3)0.86H2O,在500℃保温2h可直接生成立方相的Y2O3,煅烧至1000℃保温2h得到了结晶度高、分散性好、平均粒径为50nm、近球形的YO纳米粉体;三乙醇胺的加入有利于提高YO粉体的分散性.     

部分草酸铅法共沉淀合成Pb(Zr0.52Ti0.48)O3(PZT)粉体

结合部分草酸铅固相反应法的优点对共沉淀法进行改进,发展了一种合成锆钛酸铅(PZT)粉体新工艺.在该工艺中,首先利用共沉淀法制备Zr、Ti的羟基氧化物共沉淀((Zr0.52Ti0.48)O(OH)2,ZTOH),然后以草酸为沉淀剂,在含有ZTOH沉淀物的悬浮液中沉淀铅离子,得到合成PZT粉体的前驱体粉体.利用DTA、TG和XRD对前驱体的热分解行为和相转化过程进行了研究,利用场发射扫描电镜(FESEM)对前驱体的形貌演化进行了观察.前驱体粉体经过700℃煅烧2h,转化为晶化良好的纯相钙钛矿PZT粉体.     

溶胶凝胶法以无机锆源制备Ba(Zr,Ti)O3的成胶机理分析

为制备高性能低成本压电陶瓷材料,以无机锆为锆源,低价的乙酸与乙二醇为溶剂,采用Sol-Gel法制备Ba(Zr,Ti)O3溶胶和纳米粉体.XRD和TEM分析显示,所制备的粉体为纯钙钛矿相,近球形,粒径在40nm左右.通过IR、GC-MS分析了锆钛酸钡溶胶的形成机理,结果表明:在锆钛酸钡的溶胶过程中乙二醇、乙酸与乙酸钡、钛酸四丁酯、柠檬酸锆发生化学反应,生成以金属氧键为中心,乙二醇与冰乙酸为中间络合支架的链状聚合体,提高了溶胶凝胶的质量和稳定性.     

Ti（1-x）CoxO2的溶胶-凝胶法制备与结构

采用溶胶-凝胶方法制备了Ti（1-x）CoxO2样品。研究了不同的热处理温度和掺杂浓度对样品晶型和颗粒尺寸的影响。样品400℃热处理呈锐钛矿相，600℃转变为全红石相并且晶粒尺寸明显增大。掺杂对晶型没有影响，但是随掺杂量的增大晶格常数减小。     

Pb(Zr0.52Ti0.48)O3 nanotubes synthesis and infrared absorption properties

Herein a useful methodology to synthesize the lead zirconate titanate (PZT) nanotubes via a dip-coating deposition process with anodic aluminum oxide (AAO) template is proposed. The nano-porous AAO templates were produced using a controlled two-step electrochemical anodization technique. The PZT/AAO composite was formed using the dip-coating wetting technique. The prepared PZT precursor solution was driven into the nanopore channels of AAO template under the driving force of capillary action, subsequently the sintering process of the as-filled templates was carefully tuned to obtain Pb(Zr_0.52Ti_0.48)O₃ nanotubes of crystalline tetragonal phase with uniform pore size and ordered arrange. Fourier transform infrared spectroscopy (FTIR) results show that in the 1200–1900 cm⁻¹ band, the composite structure of PZT/AAO has obvious absorption peaks at 1471.56 cm⁻¹ and 1556.09 cm⁻¹, the absorption intensity of the composite structure is about six times of pure AAO template. The unusual optical properties found in PZT/AAO composite will stimulate further theoretical and experimental interests in ferroelectric nanostructures.     

激光脉冲外延生长Pb(Zr0.52Ti0.48)O3薄膜及其特性研究

利用激光脉冲法在LaAlO3衬底上沉积制备LaNiO3薄膜作为底电极并外延生长(100) Pb(Zr0.52Ti0.48)O3铁电薄膜,系统研究了生长温度对PZT外延结构和电学特性的影响.研究发现当生长温度高于550℃时即可得到外延(100)PZT薄膜.在对所制备的PZT薄膜的结构和性能测试表明,650℃下生长的PZT薄膜外延性最佳,并且表现出优异的介电和铁电性能,介电常数ε、剩余极化Pr和矫顽场Ec分别为900、26.5 μC/cm2和52.1kV/cm.试验还证实这种外延PZT薄膜具有优良的抗疲劳特性,可用于铁电存储器的制备中去.     

Piezoelectric and mechanical properties of Pb(Zr0.52Ti0.48)O3–Pb(Y2/3W1/3)O3 (PZT–PYW) ceramics

The piezoelectric and mechanical properties of hot-pressed PZT–PYW were investigated. As the Pb(Y_2/3W_1/3)O₃ concentration increased, the piezoelectric constant (d ₃₃) also increased up to a concentration of 3 mol% PYW reaching a value of 485×10-12 CN^-1, but beyond this concentration it continuously fell. A decrease in grain size with increasing Pb(Y_2/3W_1/3)O₃ content in the system changed the transgranular fracture mode to an intergranular fracture mode, resulting in an enhancement in K _1c from 0.83 MPam^1/2 at 1 mol% PYW to 1.1 MPam^1/2 at 3 mol% PYW. Consequently, the highest d ₃₃ and K _1c values were obtained at the composition 0.97Pb(Zr_0.52Ti_0.48) O₃–0.03Pb(Y_2/3 W_1/3)O₃. This revised version was published online in November 2006 with corrections to the Cover Date.     

Influence of Li doping on domain wall motion in Pb(Zr0.52Ti0.48)O3 films

Li-doped PbZr_0.52Ti_0.48O₃ (PZT) films were utilized to study the effect of A-site acceptor dopants on the mobility of ferroelectric domain walls. For chemical solution-deposited PZT films 2 μm in thickness doped with 1–3 mol% Li, the low-field dielectric permittivity remained between 1200 and 1300. With increasing Li concentration, the reversible Rayleigh constants ε _init increased from 1080 for undoped PZT films to 1240 for the films doped with 3 mol% Li, while the irreversible Rayleigh parameter showed a peak value at 1 mol% Li doping.