Fabrication of BaTiO_3 Inverse Opal Photonic Crystal

The colloidal crystal template or opal with a closed-packed face centered cubic (fcc) lattice, was prepared from monodisperse polystyrene (PS) spheres by gravity sedimentation. The template was used for the generation of photonic crystal. The template provided void space for infiltration of liquid precursor composed of titanium butyloxide, barium acetate, ethanol, and acetic acid. The opal composite was hydrolyzed, dried, sintered by heating for completely removing PS spheres to form BaTiO3 photonic crystals with inverse opal structure. The PS spheres were replaced by air spheres, which interconnected each other through the windows on the BaTiO3 wall. So both the BaTiO3 wall and air void constitute continuous phases.

Synthesis and Photocatalytic Property of ZnO/TiO2 Inverse Opals Films with Controllable Composition and Topology

制作控制作文、控制拓扑学的 ZnO/TiO2 反的蛋白石(IO ) 的一个新奇方法拍摄使用一个积极牺牲的 ZnO IO 模板被开发了。这个方法包括一个二拍子的圆舞过程，由简单电气化学的免职用的 ZnO IO 的准备一自己组装由液体阶段免职(LPD ) 的 ZnO/TiO2 IO 的胶体的水晶模板和准备在房间温度处理的聚苯乙烯。ZnO/TiO2 IO 的作文和拓扑学能被改变 LPD 的持续时间容易控制。在 20 min LPD 过程以后，有非拥挤不堪的以脸为中心的立方的空气范围数组的 ZnO/TiO2 合成 IO 被获得。延长持续时间到 60 min，有显然变厚的墙的纯 TiO2 IO (TIO-LPD60 ) 被形成。为组合、拓扑的变化的形成机制被讨论。为甲又蓝色的降级的样品的紫外 photocatalytic 性质上的初步的研究表明作文和拓扑学显著地影响了 IO 电影的 photocatalytic 活动。ZnO/TiO2 合成 IO 比纯 ZnO 和纯 TiO2 IO 表明活动的更高的度，尽管他们让类似的 IO 围厚度。而且，与从 ~ 增加 IO 墙厚度 52 nm 到 ~ 90 nm， TIO-LPD60 展出 photocatalytic 性能的高水平。

Hierarchically Inverse Opal Porous Scaffolds from Droplet Microfluidics for Biomimetic 3D Cell Co-Culture

With the advantages of better mimicking the specificity of natural tissues,three-dimensional(3D)cell culture plays a major role in drug development,toxicity testing,and tissue engineering.However,existing scaffolds or microcarriers for 3D cell culture are often limited in size and show suboptimal performance in simulating the vascular complexes of living organisms.Therefore,we present a novel hierarchically inverse opal porous scaffold made via a simple microfluidic approach for promoting 3D cell co-culture techniques.The designed scaffold is constructed using a combined concept involving an emulsion droplet template and inert polymer polymerization.This work demonstrates that the resultant scaffolds ensure a sufficient supply of nutrients during cell culture,so as to achieve large-volume cell culture.In addition,by serially planting different cells in the scaffold,a 3D co-culture system of endothelial-cellencapsulated hepatocytes can be developed for constructing certain functional tissues.It is also demonstrated that the use of the proposed scaffold for a co-culture system helps hepatocytes to maintain specific in vivo functions.These hierarchically inverse opal scaffolds lay the foundation for 3D cell culture and even the construction of biomimetic tissues.

Controlling the photoluminescence spectroscopy of quinacrine dihydrochloride by SiO_2 inverse opal photonic crystal

Manipulation of the photoluminescence spectra of light-emitting materials doped in three-dimensional （3D） inverse opal photonic crystals is investigated. Quinacrine dihydrochloride molecules doped highly ordered SiO2 inverse opal is successfully synthesized by co-assembly combined with double-substrate vertical infiltrate method. The quinacrine dihydrochloride-doped and-undoped SiO2 inverse opals each exhibit an apparent photonic band gap （PBG） in the visible light region. Significant suppression of the emission is observed when the PBG is overlapped with the quinacrine dihydrochloride emission bands. The mechanism of suppression effect of PBG in inverse opal on the fluorescence intensity of quinacrine dihydrochloride molecules is studied.

Photovoltaic Properties of CdSe Quantum Dot Sensitized Inverse Opal TiO₂Solar Cells: The Effect of TiCl₄Post Treatment

Recently, semiconductor quantum dot (QD) sensitized solar cells (QDSSCs) are expected to achieve higher conversion efficiency because of the large light absorption coefficient and multiple exciton generation in QDs. The morphology of TiO2 electrode is one of the most important factors in QDSSCs. Inverse opal (IO) TiO2 electrode, which has periodic mesoporous structure, is useful for QDSSCs because of better penetration of electrolyte than conventional nanoparticulate TiO2 electrode. In addition, the ordered three dimensional structure of IO-TiO2 would be better for electron transport. We have found that open circuit voltage Voc of QDSSCs with IO-TiO2 electrodes was much higher (0.2 V) than that with nanoparticulate TiO2 electrodes. But short circuit current density Jsc was lower in the case of IO-TiO2 electrodes because of the smaller surface area of IO-TiO2. In this study, for increasing surface area of IO-TiO2, we applied TiCl4 post treatment on IO-TiO2 and investigated the effect of the post treatment on photovoltaic properties of CdSe QD sensitized IO-TiO2 solar cells. It was found that Jsc could be enhanced due to TiCl4 post treatment, but decreased again for more than one cycle treatment, which indicates excess post treatment may lead to worse penetration of electrolyte. Our results indicate that the appropriate post treatment can improve the energy conversion efficiency of the QDSSCs.

CdS沉积次数对TiO_2反Opal膜电极光电性能的影响

本文以单分散聚苯乙烯(Polystyrene,简写为PS)微球为模板颗粒,采用室温漂浮自组装法组装了PS opal模板,然后用液相沉积技术填充、去除模板制备了TiO2反opal膜,最后采用化学浴沉积法(Chemistry Bath Deposition,简写为CBD)在TiO2反opal膜上沉积CdS量子点。以CdS量子点敏化的TiO2反opal膜为光阳极组装太阳能电池并测试其光电性能。实验结果表明:CBD沉积CdS量子点次数对TiO2反opal膜电极的光电性能有影响。在本文实验条件下,当CBD沉积次数为5次时,CdS量子点敏化的TiO2反opal膜电极的太阳能电池具有最高光电转化效率。

PAM-PAA microgel inverse opal photonic crystal and pH response

The colloidal crystal template or opal with a closed-packed face-centered cubic （fcc） lattice was prepared from monodisperse polystyrene （PS） spheres by vertical sedimentation. The template provided void space for infiltration of monomer precursor composed of acrylate acid, acrylamide and ammonium-persulfate, as well as microgel from the subsequent copolymerization. The sample was immersed in dimethylbenzene for completely removing PS spheres to form PAM inverse opal hydrogels （IOHPAM） or PAM/PAA inverse opal hydrogels （IOHPAM/PAA） photonic crystals. The PS spheres were replaced by air spheres, which interconnected each other through the windows. The study of responses to pH show that there are two peaks for both IOHPAM and IOHPAM/PAA films, but the IOHPAM/PAA peaks shift to higher pH, and the peaks are independent with the AA content.

TiO2反opal球形光子晶体颗粒的制备

联合萃取辅助微乳液法和液相沉积技术成功制备了TiO2反opal球形光子晶体颗粒。首先用萃取辅助微乳液法合成PSopal球形光子晶体颗粒作为模板颗粒,然后利用液相沉积技术在模板颗粒空隙填充TiO2,去除模板得其TiO2反opal结构。样品的SEM图像和反射光谱结果显示,光子晶体颗粒球形度好,组装质量较高,微观结构排列有序;反射峰狭窄陡峭,反射强度较高。

Thermal-responsive Photonic Crystals based on Physically Cross-linked Inverse Opal Nanocomposite Hydrogels

A thermal-responsive photonic crystal material was fabricated by forming an inverse opal nanocomposite hydrogel of poly(N-isopropylacrylamide)(IONHPNIPAm)within the interstitial space of a polystyrene photonic crystal template.In IONHPNIPAm,PNIPAm were physically cross-linked with two kinds of nanoparticles(carbon dots and laponite clays).The integration of carbon dots and laponite clays for physical crosslinking endowed IONHPNIPAm sufficient strength and self-healing property.IONHPNIPAm films can be completely peeled from the substrates to be utilized as an independent photonic crystal material.The structural color and optical diffraction of the IONHPNIPAm exhibits a rapid reversible change in response to external thermal stimuli due to its physical cross-linking feature.Moreover,the IONHPNIPAm shows clear fluorescence due to the introduction of carbon dots,which enables a convenient way for chemical detection(such as the detection of silver ions).This stimuli-responsive photonic crystal materials based on physically cross-linked inverse opal nanocomposite hydrogels with fast response and good mechanical stability are promising for applications in the fields of smart optical detectors,thermal-responsive sensors and chemical detectors.

TiO2光子晶体的光子带隙及其应用

最近利用TiO2光子晶体控制光子的研究取得了一定进展。本文概述了TiO2光子晶体的分类、性质、制备和应用。TiO2光子晶体在反射器件、光电转换、化学传感器和光催化等方面应用前景广阔,目前,可见光和近红外波段的TiO2光子晶体的合成是工作的难点,本文对今后TiO2光子晶体的研究提出了展望。

经济结构变动对中国碳排放影响——基于IO-SDA方法的分析

应对气候变化的进程已经在全球范围内对社会经济发展方式的根本性转变提出了要求。改革开放以来,我国产业经济结构得到了一定的改变,与其他发达国家相比,产业经济结构自身还存在较大的优化空间。本文基于1992、1997、2002、2007、2010年的投入产出表,采用IO-SDA方法(Input-Output Structural Decomposition Analysis)将碳排放量的变化分解为能源结构效应、能源强度效应、增加值效应、Leontief逆矩阵效应、最终需求效应,从而得到经济结构历史变化对于CO2排放的作用。研究结果显示,我国能源消耗导致的排放增加主要是最终需求效应与Leontief逆矩阵效应;除2002-2007年,能源强度效应始终为负,且为促进CO2排放减少的主要因素;我国终端能源结构除了1997-2002年得到了优化,其他阶段却一直在朝着高碳化的方向发展。通过构建碳排放影响力系数和碳排放感应度系数对各个部门的评价结果显示,国民经济中的基础性行业大多是高耗能的行业,未来节能减排重点需要逐步降低第二产业在国民经济中的比重,但在具体部门层次上应制定有所区别的政策:煤炭开采和洗选业等部门应保持一定的比重,不可一味降低,可更多从技术进步方面制定节能政策;通用专用设备制造业等部门可以考虑从提高能源利用效率方面改进;非金属矿物制品业等部门可以在保证人们生产生活的基础上来尽可能地降低比重;食品制造及烟草加工业等第二产业部门及房地产业至公共管理和社会组织等第三产业中的服务业部门应大力提高其在经济结构中的比重。

ZnS-opal与反opal结构ZnS光子晶体的组装

以单分散SiO2微球为基元,在75%～80%湿度、30～45℃恒温密闭烘箱中垂直快速组装opal模板;以Zn(NO3)(20.035mol/L)、TAA乙醇溶液(0.05mol/L)为前体,通过溶剂热法充填形成ZnS-opal复合光子晶体;ZnS-opal复合光子晶体在2%～5%的HF溶液中浸泡4～5h后卸载模板,制得反opal结构ZnS基光子晶体;采用XRD、SEM、UV-Vis测试手段对反opal结构ZnS基光子晶体形貌、物相和光学性能进行了表征。结果表明:溶剂热法多次充填可使ZnS纳米晶在模板密堆积形成的空隙中均匀成核;经过酸处理的ZnS-opal中SiO2微球溶解、坍塌,形成蜂窝状三维有序介孔和反opal结构ZnS基光子晶体;相同粒径SiO2微球组装的opal模板、ZnS-opal以及反opal结构ZnS光子晶体均表现出光子带隙特性,但反opal结构ZnS光子晶体带隙位置相比前两者发生了蓝移。

基于共沉积法的高结晶反蛋白石g-C_(3)N_(4)制备及其产氢性能分析

为获得光催化产氢性能优异的g-C_(3)N_(4),采用共沉积法,通过二氧化硅微球/单氰胺混合溶液制备具有高结晶反蛋白石结构的g-C_(3)N_(4),并通过扫描电镜、X射线衍射仪、红外光谱仪和比表面积及孔径分析仪等表征手段对其结构和形貌进行分析,采用气相色谱仪对其光催化产氢性能进行表征。结果表明:当二氧化硅微球/单氰胺混合溶液的离心速率为5500r/min和单氰胺溶液质量分数为70%时,所制备的高结晶反蛋白石结构的g-C_(3)N_(4)(CN5500-70%)层间距为3.23Å,比表面积为32m^(2)/g,光催化产氢性能显著提升,产氢速率为7217.01μmol/(g·h)。该方法制备的高结晶反蛋白石结构g-C_(3)N_(4)具有良好的结晶性和优异的光催化产氢活性,为g-C_(3)N_(4)基催化材料的实际应用提供参考。

在单晶硅片上直接电化学沉积制备镍反opal光子晶体

采用电化学沉积工艺直接向组装在单晶硅片上的聚苯乙烯胶体晶体中填充金属Ni,成功制备了Ni的反opal光子晶体。采用线性扫描伏安法研究了单晶硅表面的化学刻蚀对Ni的电化学沉积过程的影响,并采用扫描电子显微镜(SEM)、X射线衍射等对Ni反opal光子晶体的形貌和结构进行了观察分析,对其光学性能进行了初步研究。研究结果表明,对单晶硅片表面进行化学刻蚀有利于金属Ni的电化学沉积;在PS胶体晶体模板中电化学生长的金属Ni呈多晶状态,去除模板后形成了金属Ni的有序多孔结构。

低层数反蛋白石光子晶体薄膜的制备及光学性质研究

本文构筑了一种低层数Sn O_(2)反蛋白石光子晶体结构薄膜。基于反蛋白石光子晶体结构材料特有的有序多孔结构及慢光子效应,可有效提升光吸收,使其在太阳能电池、光催化等领域发挥出巨大的作用。本文通过无皂乳液聚合法,控制单体和引发剂的使用量,制备了3种粒径大小的聚苯乙烯(Polystyrene,PS)微球;采用垂直沉积自组装法,同时在分散液中滴加少量十二烷基硫酸钠(Sodium Dodecyl Sulfate,SDS),制备低层数PS微球蛋白石模板;最后通过牺牲模板法制备低层数Sn O_(2)反蛋白石光子晶体薄膜。该结构薄膜相比于平面结构,在具有较高的比表面积的同时,在可见光波长范围内,吸光度与漫反射率均有所提升。该反蛋白石光子晶体薄膜为设计钙钛矿太阳能电池的电子传输层提供了新策略。

二氧化钛反蛋白石膜的制备和性能调控研究进展

介绍了二氧化钛反蛋白石膜的结构特征和性能机理,总结了二氧化钛反蛋白石膜的制备方法,重点分析对比了不同应用场景下膜的性能调控思路和方法,并对二氧化钛反蛋白石膜的改进和应用发展趋势进行了展望。

Design and mechanism insight on SiC quantum dots sensitized inverse opal TiO_(2) with superior photocatalytic activities under sunlight

The combination of SiC quantum dots sensitized inverse opal TiO_(2) photocatalyst is designed in this work and then applied in wastewater purification under simulated sunlight.From various spectroscopic techniques,it is found that electrons transfer directionally from SiC quantum dots to inverse opal TiO_(2),and the energy difference between their conduction/valence bands can reduce the recombination rate of photogenerated carriers and provide a pathway with low interfacial resistance for charge transfer inside the composite.As a result,a typical type-II mechanism is proved to dominate the photoinduced charge transfer process.Meanwhile,the composite achieves excellent photocatalytic performances(the highest apparent kinetic constant of 0.037 min^(-1)),which is 6.2 times(0.006 min^(-1))and 2.1 times(0.018 min^(-1))of the bare inverse opal TiO_(2) and commercial P25 photocatalysts.Therefore,the stability and non-toxicity of SiC quantum dots sensitized inverse opal TiO_(2) composite enables it with great potential in practical photocatalytic applications.

大尺寸TiO_2反蛋白石结构的制备及性能分析

针对蛋白石结构光子晶体不能产生完全光子带隙的问题,采用垂直沉积法制备出单分散聚苯乙烯(PS)蛋白石结构胶体晶体模板,向模板填充TiO_2溶胶制成PS/TiO_2复合结构,将其放置在450℃的电炉中高温煅烧2h,得到了TiO_2反蛋白石结构.通过扫描电镜、吸收光谱仪和偏光显微镜对煅烧后的材料进行了测试和表征.结果表明:制备得到的TiO_2反蛋白石薄膜为厘米尺度范围内排列周期有序的大孔结构,孔径可控且选择范围宽.结构骨架表面平整,缺陷很少,几乎不存在塌陷.薄膜的透射光谱带隙窄,深度大,峰值尖锐,证实了样品内部结构的高质量和有序性.

反Opal及二维非线性光子晶体的研究(英文)

通过向SiO2 Opal模板中填充钛酸乙酯制备TiO2光子晶体，观测到光子晶体带隙位置的移动达62nm，并发现光子晶体的有序度随填充率的升高而下降．向聚苯乙烯Opal模板中填充钛酸乙酯，制备成当时填充率最高、带隙最短的紫外波段TiO2反Ova光子晶体（中心波长～380nm），并根据测量的其透射谱估算出其填充率约为12％，即Opal模板孔隙的50％被填充．本文还对二维PPLN光子晶体进行了研究．建立了一套高压极化装置和电压数据采集装置，通过外加电场极化法成功制备出了具有正方形和矩形两种晶格形状二维PPLN光子晶体．利用二维PPLN的二阶准相位匹配，测量了其对1．064μm激光的二次谐波转换效率，并研究了晶体的温度、激光的入射角度及占空比对二次谐波转换效率的影响．利用矩形晶格实现了多方向、多波长倍频高效输出．

Conductive PS inverse opals for regulating proliferation and differentiation of neural stem cells

The development of neural tissue engineering has brought new hope to the treatment of spinal cord injury(SCI).Up to date,various scaffolds have been developed to induce the oriented growth and arrangement of nerves to facilitate the repair after injury.In this work,a conductive and anisotropic inverse opal substrate was presented by modifying polystyrene(PS)inverse opal films with carbon nanotubes and then stretching them to varying degrees.The film had good biocompatibility,and neural stem cells(NSCs)grown on the film displayed good orientation along the stretching direction.In addition,benefiting from the conductivity and anisotropy of the film,NSCs differentiated into neurons significantly.These results suggest that the conductive and anisotropic PS inverse opal substrates possess value in nerve tissue engineering regeneration.