金属β-二酮化合物用于MOCVD法生长铁电氧化物薄膜

对用于MOCVD法生长铁电氧化物薄膜的金属β－二酮化合物的制备、结构及性质进行了评述，对它们在生长铁电薄膜中的应用现状进行了介绍，并对它们的应用前景作了展望。     

MOCVD生长铁电氧化物薄膜MO源研究进展

高性能铁电氧化物薄膜是当今功能材料的研究热点之一.随着新型MO源的不断研究与开发,利用MOCVD技术制备高质量铁电薄膜材料得到了快速的发展.本文在分析金属醇盐和金属β-二酮化合物等MO源的结构与其物性依赖关系基础上,分类综述了近年来在用于MOCVD方法生长铁电氧化物薄膜的新型MO源研究和开发方面的发展动态与趋势,为MOCVD方法制备铁电薄膜材料MO源的选择提供有用的参考与借鉴.     

PZT铁电薄膜底电极制备工艺的研究

利用磁控溅射方法在Si(001)基片上制备Ti/Pt底电极,其厚度大概分别为20、100 nm,其中Ti电极作为缓冲层,随后在上面溅射PZT铁电薄膜.研究了不同电极的制备工艺对电极形貌、取向以及对PZT铁电薄膜的制备带来的影响.结果表明,底电极的溅射温度以及退火温度对于底电极起着至关重要的作用,同时具有良好(111)取向的、致密性较好的底电极对于PZT铁电薄膜的生长具有重要的影响.     

钙钛矿铁电纳米片诱导的P(VDF-TrFE)取向生长（英文）

半结晶的铁电聚合物在柔性电子器件中极具应用前景,控制晶相生长对其性能优化至关重要。本文通过引入少量(0.2%)单晶单畴的PbTiO_3纳米片对P(VDF-TrFE)(简称PVTF)铁电薄膜的生长进行有效调节,获得了高度取向的铁电薄膜且铁电性能得到了大幅提高。PbTiO_3纳米片铁电极化对PVTF极性分子的诱导作用可能是薄膜取向生长与性能提高的原因。     

无机多核过渡金属氰化物薄膜修饰电极的新进展

本文对普鲁士兰类无机多核过渡金属氰化物薄膜化学修饰电极的近年发展及其在电催化，电色效应，离子选择性电极和生物活体分析等方面的应用进行了评述，引用文献50篇。     

盘状多酸P_5W_(30)/阳离子聚电解质/氧化石墨烯杂化多层膜的电致变色性能

为了提高薄膜[PEI/P_5W_(30)]_(30)的电致变色性能,将具有大的二维尺寸和良好导电性的氧化石墨烯引入该薄膜中。通过层层自组装(LBL)技术构筑了基于盘状多酸K12.5Nal.5[Na P_5W_(30)O_(110)]·15H_2O(P_5W_(30))、氧化石墨烯(GO)的复合薄膜[PEI/P_5W_(30)/PEI/GO]_(30)(PEI:聚乙烯亚胺),并利用UV-Vis光谱对薄膜的组成及增长进行监测;通过原子力显微镜对薄膜的表面形貌进行考察,利用循环伏安法对薄膜电化学氧化还原性质进行研究;薄膜在外加氧化还原电位下呈现出无色/蓝色的可逆变化,电致变色响应时间在10 s以内;此外,薄膜在阶跃电位0.75 V/-0.75 V下循环150次,电致变色性能没有明显减弱,体现了薄膜良好的电致变色可逆性。氧化石墨烯的引入使薄膜[PEI/P_5W_(30)/PEI/GO]_(30)呈现出响应速度快、抗电疲劳强的电致变色性能,将在电致变色器件领域有广阔的应用前景。     

低含量铁掺杂纳米TiO2薄膜的制备及其抗菌机理研究

采用溶胶凝胶-浸渍提拉法,制备了玻璃基底上生长的Fe/TiO₂薄膜.利用XRD、XPS、AFM等对样品进行表征,研究了铁掺杂对TiO₂薄膜晶体结构和表面形貌的影响,并研究了不同掺铁量TiO₂薄膜对大肠杆菌的抗菌性能.结果表明,铁掺杂TiO₂薄膜的抗菌性能均优于纯TiO₂薄膜,其中掺铁量为0.1%时薄膜的抗菌性能最佳,高达98%.     

液晶的最新进展──金属有机铁电液晶

对金属有权液晶的分子形状、合成和性能进行了评述，为提高金属有机铁电液晶分子的偶极矩和电光响应速度进行了新的探索和分子设计。     

氢氧化镍薄膜制备及析氧电催化活性评价的综合实验设计

设计一个包括氢氧化镍薄膜制备、铁掺杂以及析氧电催化活性评价的系统性应用化学综合实验。通过开展本实验,学生能够(1)学习利用电化学沉积方法制备电催化剂薄膜的技术;(2)初步掌握利用循环伏安、塔菲尔曲线等电化学测试技术对析氧电催化剂的活性进行评价的方法;(3)认识到痕量的杂质元素(铁)将对物质性能(析氧电催化活性)产生显著影响的客观事实。本实验将引导学生关注绿色可再生能源的开发及应用,有利于学生化学应用能力的培养。     

旋转涂布法制备Si-Mo-W酸盐电致变色薄膜

本文采用旋转涂布制备了Si-Mo-W酸盐的电致变色薄膜。伴随着Li⁺的电化学注入，这些薄膜呈现出可逆的颜色变化。由于这类电致变色薄膜的变色幅度较小，故可用作为强变色材料的对电极。     

Epitaxial oxide thin films by pulsed laser deposition: Retrospect and prospect

Pulsed laser deposition (PLD) is a unique method to obtain epitaxial multi-component oxide films. Highly stoichiometric, nearly single crystal-like materials in the form of films can be made by PLD. Oxides which are synthesized at high oxygen pressure can be made into films at low oxygen partial pressure. Epitaxial thin films of highT _c cuprates, metallic, ferroelectric, ferromagnetic, dielectric oxides, superconductor-metal-superconductor Josephson junctions and oxide superlattices have been made by PLD. In this article, an overview of preparation, characterization and properties of epitaxial oxide films and their applications are presented. Future prospects of the method for fabricating epitaxial films of transition metal nitrides, chalcogenides, carbides and borides are discussed.     

Precise Control of Metal Oxide Thin Films Deposition in Magnetron Sputtering Plasmas for High Performance Sensing Devices Fabrication

Magnetron sputtering deposition is a widely used technique to deposit thin film precisely at nanoscale level. During the deposition of metal oxide thin films, reactive oxygen gas is introduced into the deposition chamber. Pure metal and metal oxide materials can be used as sputter target, although the simplest way is by using a pure metal target. In such reactive process, the effect of target poisoning significantly influence the deposition process and the growth mechanisms of metal oxide thin films became very complex. In general, external parameters such as discharge power, working pressure, reactive gases ratio and substrate temperature are used to optimize the properties of deposited thin films. Then, ex-situ analyses such as scanning electron microscope and X-ray diffraction analysis are performed to obtain the optimized parameter. Sample depositions and ex-situ analyses consume time to achieve the goal through try and error. In this article, in-situ plasma diagnostics are reviewed focusing on an optical emission spectroscopy to precisely control and investigate the sputter target poisoning effect during the deposition of metal oxide thin films. The emission of atomic lines from several metal and oxygen atoms were used to discuss the deposition mechanisms and their correlation with the deposited thin films was observed. Finally, the deposited metal oxide thin films were proposed and tested for several applications such as gas sensor and frequency selective surface glass.     

Magnetoelectric Bi3.25Nd0.75Ti3O12–La0.6Ca0.4MnO3 composite thin films derived by SOL–GEL method

Magnetoelectric (ME) Bi_3.25Nd_0.75Ti₃O₁₂–La_0.6Ca_0.4MnO₃ (BNT–LCMO) composite thin films were deposited on Pt/Ti/SiO₂/Si(100) substrates by a simple SOL–GEL method and spin-coating process with two different deposition sequences: BNT/LCMO/Pt/Ti/SiO₂/Si(BLP) and LCMO/BNT/Pt/Ti/SiO₂/Si(LBP). Our results show the composite thin films exhibit both good ferroelectric and magnetic properties, as well as a ME effect. BLP thin films have larger maximum ME voltage coefficient values than LBP structured thin films. The deposition sequence has a notable effect on the ferroelectric and magnetic properties and ME coupling behavior of the bi-layer thin films.     

Ferroelectric ceramics by sol–gel methods and applications: a review

New advances in the sol?Cgel processing of ferroelectric ceramic powders and thin films and recently, scientific and technological interests in ferroelectric ceramics have been focused particularly on thin films. This is mainly due to their great potential applications in integrated electronics as passive components and as non-volatile ferroelectric memories, optoelectronic devices, etc. Special attention has been paid to the effects of the microstructure and composition on the piezoelectric properties of ferroelectric ceramic powders and thin films, and various characterization techniques are reported. This paper introduces the basic principles governing ferroelectricity and lists the various materials which exhibit these properties. The processing of ferroelectric ceramics and thin films in general and sol?Cgel processing in particular, with some examples are described. Finally, important applications of ferroelectric films and microstructure examination as well as powerful techniques are briefly discussed.     

Characterization and electrochemical deposition of natural melanin thin films

Melanin is an important class of biological pigments because of its distinct chemical and physical properties. The electrochemical deposition of natural melanin thin films was studied using two different techniques; constant potential and cyclic voltammetry along with a deposition time of five hours. The thin films deposited electrochemically on a fluorine-doped tin oxide conductive glass substrate using the constant potential method, exhibited faster growth rate and better adhesion to the fluorine-doped tin oxide working electrodes than those deposited using the cyclic voltammetry method. The thin films deposited on the fluorine-doped tin oxide conductor glass using the constant potential method were also more homogeneous than those deposited via the cyclic voltammetry technique. The increase of film thickness is related to the increase of electrochemical deposition time. Interestingly, the electrochemical deposition using the constant potential method had the advantage of consuming less electric charge. The physical and chemical structures of the melanin thin films were characterized using ultraviolet–visible absorption spectroscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction analysis. The ultraviolet–visible absorption spectra showed the correlation between the variation of deposition rates of melanin and the type of electrochemical technique employed as well as the thickness of the film. The average thickness of the film is 500 nm which absorb 40% of light in both type of films. The atomic force microscopy images illustrated the homogeneous deposition of the melanin molecules on the fluorine-doped tin oxide conductive glass substrate, indicating that the thickness of the thin films can be controlled. We estimated an average grain size of 14.093 Å. The ease of preparing such thin films of organic materials can open new avenues towards the use of soft conductors, in contrast to the complex preparation of industrial semiconductors.     

LaNiO3衬底上Pb(ZrxTi1－x)O3铁电薄膜及梯度薄膜的制备和研究

报道了在镍酸镧 (LaNiO₃, 简称LNO)衬底上锆钛酸铅 [Pb(Zr_xTi_1－x)O₃, 简称PZT]铁电薄膜及其成分梯度薄膜的结构、介电性能、铁电性能以及热释电性能. 首先通过金属有机化合物热分解(MOD)法在Si(100)基片上制备出LaNiO₃, 薄膜, 再通过溶胶-凝胶(sol-gel)法, 在LNO/Si(100)衬底上制备出Pb(Zr_0.80Ti_0.20)O₃, [PZT(80/20)]和Pb(Zr_0.20Ti_0.80)O₃, [PZT(20/80)]铁电薄膜及其成分梯度薄膜. 经俄歇微探针能谱仪(AES)对制备的梯度薄膜进行了成分深度分析, 结果证实成分梯度的存在. 经XRD分析表明, 制备的梯度薄膜为四方结构和三方结构的复合结构, 但其晶面存在一定的结构畸变. 经介电频谱测试表明, 梯度薄膜的介电常数比每个单元的介电常数要大, 但介电损耗相近. 在10 kHz下, 梯度薄膜的介电常数和介电损耗分别为317和0.057. 经电滞回线的测试表明, 梯度薄膜的剩余极化强度比每个单元都大, 而矫顽场却明显较小. 梯度薄膜的剩余极化强度和矫顽场分别为29.96 μC•cm^-2 和54.12 kV•cm^－1. 经热释电性能测试表明, 室温下梯度薄膜的热释电系数为5.54×10-8 C•cm^－2•K^－1, 高于每个单元的热释电系数.     

Facile deposition of high quality ferroelectric poly(vinylidene fluoride) thin films by thermally modulated spin coating

Direct deposition of high quality ferroelectric PVDF thin films using a modulated temperature spin coating method is demonstrated. The method is qualitatively guided from Flory‐Huggins theory of polymeric solutions and is general in applicability. Ferroelectric PVDF films with similar high structural and dielectric quality are deposited in environments ranging from 20 to 80% relative humidity on polar and non‐polar surfaces. The films do not show the presence of the non‐ferroelectric α‐phase. Resultant films have rms roughness values lower than 16 nm and remnant polarizations up to 6.5 µC cm^?2. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55 , 221–227     

Possibilités d'obtention de dépôts dans le système céramique ti-v-c-n à partir de sources moléculaires

Monometallic and heterobtmetallic titanium and vanadium compounds were prepared and studied as precursors to the chemical vapor deposition (CVD) of carbide and nitride ceramic thin films. Their thermal properties are discussed according to the chemical environment of the metal atom and their CVD behavior is studied. Two of them, CpTiCl₂N(SiMe₃)₂ and Cp₂VMe₂, are applied to the deposition of thin films within the Ti-V-C-N quaternary system.     

Ferroelectric Materials by the Sol-Gel Method

The sol-gel method is ideally suitable for the preparation of ferroelectric thin films such as LiNbO₃, BaTiO₃, KNbO₃ and PZT. The preparation and properties of polycrystalline, amorphous and single crystal films of these ferroelectric oxides are summarized. The origin of “amorphous ferroelectricity” is discussed. Single crystal KNbO₃ films have been successfully fabricated into planar waveguides and their ability to convert infrared laser into green light demonstrated.