胶粒晶体模板法制备三维有序大孔材料

使用胶粒模板法制备三维有序大孔材料（three-dimensional ordered macroporous material,3DOM）是一个快速发展的领域。本文综述了3DOM的合成技术,包括各种填充模板的方法、模板的去除方法以及它们在光子晶体、催化材料、生物传感器以及医学等方面的应用前景。     

自组装方法与三维光子晶体制作

光子晶体,特别是三维光子晶体,可能成为信息处理和通信等领域的新型功能材料.光子晶体的制作方法可分为"自上而下"的物理方法和"自下而上"的化学自组装方法.化学自组装方法是制作三维光子晶体最为经济有效的方法.本文在阐述自组装方法的种类、一般过程、优点和不足等内容的基础上,分别分析和总结了带有各种功能缺陷的三维光子晶体的制作,这些缺陷主要包括线缺陷、面缺陷和点缺陷.从研究中可以看出,化学自组装方法通常需要结合其他方法才能实现缺陷的嵌入.近些年,三维光子晶体制作在材料选取、结构设计和方法改进等方面都有一些最新进展,本文对此进行了较为详尽的评述,并对我们课题组的研究进行了总结.最后对光子晶体的研究和制作方向进行了展望.     

胶体晶体研究进展

重点阐述了有关胶体晶体的制备方法、以胶体晶体为模板制备的大孔材料，以及利用胶体晶体的三维有序结构、结构颜色等特性制备光子晶体、传感器等研究的进展。     

二维光子晶体

光子晶体是一种介电常数周期变化的功能材料,其基本特征是具有光子带隙。光子晶体理论诞生已三十年,基于理论及实验的研究取得了许多成绩。当所制备的光子带隙与光波的波长相当时,光子晶体材料抑制光子在一定频段内的传播。由于在光学、电学、热学、磁学等方面均有优良特性和潜在应用,光子晶体作为一种新型材料也越来越受到科研人员的青睐。不论在可加工性方面还是在传播特性方面,二维光子晶体的优势正逐渐体现出来。本文重点阐述二维光子晶体的研究进展,分别介绍了二维光子晶体的结构与性能特点以及近年来发展出的新型制备方法,如自组装法、刻蚀法、多光束干涉法等,并着重列举其在传感器、波导、光纤、太赫兹技术等领域的发展现状,表明二维光子晶体作为超材料具有巨大的发展空间和潜力。最后,本文对二维光子晶体今后的研究方向和发展前景作了展望。     

电场响应光子晶体

光子晶体是一种介电常数周期变化、具有光子带隙、对光路可控的新型功能材料。将对外界刺激敏感性材料引入光子晶体空隙就得到可响应光子晶体。电场响应光子晶体是由电活性材料与光子晶体结构相结合所得,可以应用于反射型彩色显示并表现出其他显示技术所没有的独特优点。本文重点介绍了电场响应光子晶体器件的结构和响应机理,并按照引入电活性材料的不同将电场响应光子晶体分为基于液晶、聚电解质水凝胶、金属有机聚合物凝胶、导电聚合物以及核壳式电场响应光子晶体,总结了近几年各类电场响应光子晶体的研究进展,提出了在反射型彩色显示器件方面的应用以及存在的问题和展望。     

垂直排列法组装胶体晶体的最新进展

光子晶体是一种具有光子带隙的新型功能材料.利用胶体粒子自组装三维光子晶体由于其制备过程比较经济、简单,从而为很多人所关注.目前报道的方法已有多种.其中垂直排列法的简便易行使得其受到了广泛的研究,但另一方面这种方法本身的缺点也限制了它的使用范围.针对这种情况,很多研究机构提出了他们的改进方法.本文简要概述了在这一方面的最新进展,并且在本实验室已能够制备任意单分散、均一尺寸二氧化硅粒子的基础上,采用恒温快速蒸发自组装法得到了高质量的胶体晶体排列.     

光子晶体结构色材料的自组装制备与应用

光子晶体是由不同折射率材料周期性排列而成的结构,由于其独特的光学性质及优异的色彩饱和度,已经成为结构色材料中最重要的类型.过去几十年来,纳米粒子自组装制备光子晶体具有精准、成本低以及易大面积等优势,已经得到了广泛的研究和关注.综述了近期光子晶体结构色材料的研究进展,包括其基本的生色机制,制备方法以及在显示、色度传感和信息防伪加密等方面的实际应用.其中重点讨论了“自下而上”自组装的制备方式,并且强调了图案化和大面积结构色材料的制备方法.最后,对目前自组装制备光子晶体结构色材料所面临的挑战以及未来发展的方向进行了展望.     

化学响应性光子晶体

光子晶体是一种具有光子带隙结构的周期性电介质材料,如果将响应性材料组装到光子晶体结构中,所形成的光子晶体的带隙结构则对外界环境的变化具有响应性,而被称为响应性光子晶体。响应性光子晶体作为光子晶体的一个新领域,由于其在传感器,生物医学,临床检测等方面的潜在应用,近几年受到广泛关注。根据外界环境的不同,响应性光子晶体可简单分为化学响应性光子晶体、物理响应性光子晶体和生物响应性光子晶体等。本文将对化学响应性光子晶体的国内外研究动态做一简要介绍,重点介绍以下五种化学响应性光子晶体:金属离子响应光子晶体、pH响应光子晶体、氧化还原响应光子晶体、葡萄糖响应光子晶体和光化学响应光子晶体。     

金属基光子晶体的研究进展

以具有独特功能的金属基材料（或其氧化物）及复合材料作为构筑单元制备的金属基光子晶体展现出优良的光学性能及光电转化性能,这对于拓展光子晶体在未来新型能源开发领域的应用前景具有重要意义. 综述了金属基光子晶体的制备方法、性能研究及其应用进展,并对金属基光子晶体在未来新型能源开发等方面的应用前景进行了展望.     

胶体晶体

简要综述胶体晶体的研究进展情况,主要介绍胶体粒子的简单自组装、模板引导下的自组装和二元胶体晶体组装等几类主要的胶体晶体制备技术,并概述胶体晶体在光子晶体、传感器、光子纸张、三维有序大孔材料、二维纳米结构阵列等方面的应用。     

蛋白石及反蛋白石結構光子晶體

光子晶体是由不同介电常数的材料构成的一种空间周期性结构，它能够在特定方向上禁阻、控制和操纵光子的运动。目前，已制备的光子晶体具有几种不同的结构类型，本文主要综述了蛋白石、反蛋白石结构光子晶体的制备方法及其光子带隙的影响因素。     

Recent advances in fabrication of monolayer colloidal crystals and their inverse replicas

Monolayer colloidal crystals(MCCs)are two-dimensional(2D)colloidal crystals consisting of a monolayer of monodisperse colloidal particles arrayed with a 2D periodic order.In recent years,MCCs have attracted intensive interest because they can act as 2D photonic crystals and be used as versatile templates for fabrication of various 2D nanostructure arrays.In this review,we provide an overview of the recent progress in the controllable fabrication of MCCs and their inverse replicas.First,some newly-developed methods for the self-assembly of MCCs based on different strategies including interfacial assembly and convective assembly are introduced.Second,some representative novel methods regarding the fabrication of various functional2D inverse replicas of MCCs,such as 2D arrays of nanobowls,nanocaps,and hollow spheres,as well as 2D monolayer inverse opals(MIOs),are described.In addition,the potential applications of MCCs and their inverse replicas are discussed.     

Fabrication of 3D polymeric photonic arrays and related applications

This review article describes the state-of-art methodologies, mainly self-assembly routes, which are in practice to fabricate photonic crystals (PCs) for advanced applications. The self-assembly of colloidal building blocks is an effective, affordable, and tunable approach to fabricate varieties of photonic materials of desired shapes and surface areas. Because of easy fabrication and controlled performance factors, PCs emerged as a potential platform for designing and developing optical devices with desired features such as photonic bandgap, high reflectance/transmittance, low loss, and lasing in the visible range of wavelengths. To develop next-generation optoelectronics and optical system, significant efforts are being made to explore novel and cost-effective fabrication methods to design and develop 3D-PCs platform, which is covered in this mini-review. The challenges, potential alternatives, and prospects of self-assembled 3D PCs are also discussed in this review.     

Photoswitching properties of photonic band gap material containing azo-polymer liquid crystal

A photochemically tunable photonic crystal was prepared by infiltration of the polymer liquid crystal (LC) having azo-chromophores in a SiO₂ inverse opal structure. The SiO₂ inverse opal film infiltrated with the polymer LC reflected a light corresponding to the periodicity as well as the refractive indices of the inverse opal structure. Linearly polarized light irradiation caused the shift of the reflection band to longer wavelength more than 15 nm. This is caused by the formation of uniaxially anisotropic molecular orientation of the polymer LC. The switched state was stable under interior light, and reversible switching of the reflection band can be achieved by the linearly and circularly polarized light irradiation. This photoswitching property will be suitable not only for various optical materials, but also for introduction of defects in the photonic crystals.     

Polarized IR spectra of the hydrogen bond in acetic acid crystals

The paper presents the results of our investigations of the polarized IR spectra of the hydrogen bond in crystals of acetic acid, CH₃COOH, as well as in crystals of three deuterium isotopomers of the compound: CH₃COOD, CD₃COOH and CD₃COOD. The spectra were measured at 283 K and at 77 K by a transmission method using polarized light. Theoretical analysis of the results concerned the linear dichroic effects, together with the H/D isotopic and temperature effects observed in the solid-state IR spectra of the hydrogen and of the deuterium bond at the frequency ranges of the ν_O–H and the ν_O–D bands, respectively. Basic spectral properties of the crystals can be interpreted satisfactorily in terms of one of the quantitative theories of the IR spectra of the hydrogen bond, i.e. the “strong-coupling” theory or the “relaxation” theory when a hydrogen bond dimer model is used. From the spectra obtained it resulted that the strongest exciton coupling involved the closely spaced hydrogen bonds, belonging to different chains of associated acetic acid molecules. These results contradict the former explanation of the spectra within a model, which assumed a strong vibrational exciton coupling between four hydrogen bonds in a unit cell. On analyzing the spectra of isotopically diluted crystalline samples of acetic acid it has been proved that a non-random distribution of the protons and deuterons takes place in the hydrogen bond lattices. This non-conventional isotopic effect is a result of dynamical co-operative interactions involving hydrogen bonds in the system. Simultaneously it has been also found that in an individual hydrogen bonded chain in the crystals, distribution of the hydrogen isotope atoms H and D was fully random. The H/D isotopic “self-organization” mechanism most probably involves a pair of hydrogen bonds from each unit cell where each hydrogen bond belongs to a different chain.     

微凝胶胶体晶体研究进展

Poly(N-isopropylacrylamide)(PNIPAM)微凝胶粒子是一种软的胶体粒子.和单分散的SiO_2、PS、PMMA等硬的胶体粒子一样,单分散的PNIPAM微凝胶粒子也可以自组装成为高度有序的胶体晶体.微凝胶粒子软物质的特性及其对外部刺激的响应性赋予其不同于硬球的组装行为.微凝胶胶体晶体的高度有序结构及其刺激响应性使其在诸多领域有重要用途.本文分别介绍了三维及二维微凝胶胶体晶体组装的研究进展,并对已开发的基于微凝胶胶体晶体的应用进行了总结.     

Fabrication and characterization of core-shell photonic crystals via a dipping process

High-quality polystyrene (PS) colloidal photonic crystals in large area were fabricated in 24 h via a capillary-enhanced process. Then, the photonic crystals with core-shell structure were obtained by incorporating silica nanoparticles into the interstitial space of opal template via a dipping process. The filling ratio (V_silica) of interstitial space could be manipulated by dipping colloidal crystals into suspensions with different concentrations of silica nanoparticles, which in turn renders the obtained core-shell photonic crystals. The absorptive peak of opal without dipping process is at 445 nm as measured by UV–vis spectrometry. The filling ratios of 0.130, 0.167 and 0.253 can be calculated according to the modified Bragg's Law, which corresponds to the absorptive peaks for core-shell opals at 453, 463 and 469 nm obtained from suspensions with silica nanoparticles of 0.017, 0.122, and 0.244 wt%, respectively. Therefore, by using this dipping process, the characteristic absorption wavelength for photonic crystal will be varied easily, efficiently and cost effectively than that by traditional methods for constructing opal from monodispersed colloids of different diameters.