溶胶浸渍模板法制备有序多孔氧化钛、氧化锌薄膜

采用溶胶浸渍模板法制备了有序多孔的氧化钛(TiO₂)和氧化锌(ZnO)薄膜。首先，在洁净的玻璃基片上通过浸渍-提拉工艺组装有序的聚苯乙烯微球(PS)阵列模板；然后再采用溶胶浸渍法将TiO₂和ZnO溶胶灌充到PS模板微球的间隙内；最后通过煅烧去除PS而得多孔薄膜。采用SEM观察了薄膜的表面形貌，并用XRD对薄膜的性能进行了表征。结果表明，溶胶的浓度对薄膜形貌有着显著的影响。经煅烧后，TiO₂和ZnO薄膜分别为锐钛矿和六方纤锌矿结构。此外，对模板的组装及溶胶的灌注过程进行了分析。     

溶剂散逸自组装制备高分子有序微透镜阵列

利用水珠为模板制备了聚苯乙烯有序多孔膜.在溶剂挥发的制冷作用下,水珠能够在冷的高分子溶液表面凝结形成有序的阵列,溶剂蒸发完毕后,高分子材料按照水珠排列形貌空隙形成有序多孔膜,一种两性共聚物被加入到溶液中稳定水珠而获得有序的多孔结构. 将聚乙烯醇水溶液填充入多孔膜中,蒸干后用氯仿洗去聚苯乙烯,得到聚乙烯醇的整球微透镜阵列. 聚苯乙烯有序针垫阵列是由有序多孔膜撕掉上层制备的,这种针垫结构内部具有半球结构的空间,并以此为模板制备了聚乙烯醇半球微透镜阵列. 2种微透镜阵列均具有微观显影功能. 通过2种微透镜的显像对比证实,半球微透镜阵列比整球微透镜阵列具有更为清晰的多重显像效果.     

多孔氧化铝有序膜的制备研究

本文用阳极氧化法分别在硫酸和草酸电解液中成功制备出高度有序、具有纳米级孔洞的氧化铝有序阵列模板。采用饱和HgCl₂去除Al基体后,得到典型六方形结构的多孔Al₂O₃有序膜。通过改变氧化电压、氧化时间等条件使模板的孔径、孔深可调、膜厚度可控,并系统研究了对模板有序性、孔径、膜厚度等的影响因素,总结出制备Al₂O₃有序膜的最佳工艺。     

反应性模板法合成硫化银中空球-银纳米粒子异质结构

以Cu₂S中空球为反应性模板, 通过在水溶液中与银离子的阳离子交换和氧化还原反应制备了大小均匀的Ag₂S中空球-Ag纳米粒子异质结构, 即Ag₂S-Ag异质中空球. 该异质结构中每个Ag₂S中空球的直径约为600 nm, 壁厚约20–30 nm, 其表面均附着一个Ag纳米粒子. 采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)和能量色散X射线谱(EDS)对所得Ag₂S-Ag异质中空球的结构和组成进行了表征. 若以CuS中空球为反应性模板, 在相似转化条件下则主要得到不含Ag粒子的Ag₂S中空球. 该结果表明, Cu₂S中的Cu(I)的还原性在Ag₂S-Ag异质中空球的形成中发挥了重要作用. 通过对所制备的Ag₂S-Ag异质中空球进行二次生长, 还可以得到Ag₂S中空球的半球表面均被Ag膜所包覆的Ag₂S-Ag异质中空球.     

NiO纳米片和多孔纳米片自组装的空心微球的无模板水热法制备与磁学性质

报道一种非常简单的制备NiO和Ni(OH)₂空心微球的无模板水热法, 即通过NiCl₂与氨水在140 ℃水热反应12 h, 制备了Ni(OH)₂纳米片自组装的空心微球, 经400 ℃热处理2 h得到了NiO空心微球. 采用X射线衍射仪、扫描电镜和透射电子显微镜对产物进行表征, 并在室温下测试了它的磁学性能, 结果表明, Ni(OH)₂空心微球的直径约为3～4 μm, 它是由尺寸1.1～1.3 μm左右的六方相结构的Ni(OH)₂纳米片组装而成; NiO空心微球是由立方相纳米片和多孔纳米片组装而成, 它具有弱的铁磁性, 其矫顽力为583 Oe, 剩余磁化强度为0.213 emu/g. 研究了氨在Ni(OH)₂纳米片的形成与组装过程中的作用, 提出了可能的生长机理.     

氧化钼-二氧化钛复合膜的可见光致变色性能研究

采用溶胶凝胶法制备了一系列氧化钼-二氧化钛纳米复合物, 用柠檬酸作分散剂, 将得到的纳米复合物粉末分散成溶胶, 涂膜制备了具有可见光变色性能的均匀透明的光致变色(λ≥420 nm)复合膜. 通过红外、XPS、ESR测定表明, 在氧化钼、二氧化钛复合界面上生成了Mo—O—Ti键, 此键的存在是该复合膜具有可见光致变色响应的内在原因. 在可见光的照射下, 电子从二氧化钛的价带经由Mo—O—Ti键, 被激发到氧化钼的导带上. 研究了光致变色过程的动力学, 发现光致变色反应的速率取决于膜中复合物的摩尔比([MoO₃]/[TiO₂])以及电荷转移能量(CTE).     

二氧化钛反蛋白石薄膜的制备及其在化学传感器中的应用

用提拉成膜法将单分散295 nm聚甲基丙烯酸甲酯(PMMA)胶体微球自组装成蛋白石光子晶体膜. 在PMMA蛋白石光子晶体膜的空隙里填充15 nm二氧化钛纳米颗粒, 经500 ℃的处理除去PMMA膜板, 制备出大面积, 结构均一的二氧化钛反蛋白石光子晶体膜. 扫描电子显微镜(SEM)观察和X射线光电能谱(XPS)分析表明, 这种二氧化钛反蛋白石光子晶体薄膜是六方紧密堆积. 用这种二氧化钛反蛋白石光子晶体膜对溶液折射率的检测实验表明该传感膜分辨率可达0.01.     

竹节状碳纳米管有序阵列的合成和表征

用1,4-偶氮二异丁基腈作碳源,以载有催化剂Co的多孔Al₂O₃膜作模板,用化学气相沉积法在较低温度(600℃)下方便地制得了单分散碳纳米管有序阵列。透射电子显微分析表明,所得碳纳米管的形态为竹节形状,端口是闭合的,这和同样用Al₂O₃膜作模板但以乙烯或乙炔作碳源热分解制得的中空碳纳米管的情形明显不同。对该纳米管的生成机理进行了初步探讨。     

SnCl4对纳米二氧化钛晶相结构的低温转变控制研究

采用二种方法制备了低温下晶相结构可控制转变的纳米二氧化钛。一种方法是采用乙醇作溶剂的溶胶-凝胶法,通过控制SnCl₄的添加量,便可在450℃热处理下实现纳米TiO₂从纯锐钛矿到不同比例的复合相直至纯金红石相的转变。另一种方法是采用钛酸丁酯为原料直接低温水解,通过加入不同量的SnCl₄,制备了具有晶态结构的二氧化钛复合溶胶,在120℃下干燥处理便可实现TiO₂从锐钛矿到不同比例的复合相(金红石型、锐钛矿型和板钛矿型)直至纯金红石相的转变,制备所需晶态结构的纳米TiO₂。所有样品进行了透射电镜与XRD表征,制备的纳米TiO₂及其TiO₂-SnO₂纳米复合材料颗粒小、分布均匀、分散性好,没有检测到SnO₂晶体的X-衍射特征峰。     

溶剂散逸自组装法制备具有电致收缩性能的聚苯胺/聚氨酯凹透镜阵列

以水珠为模板,采用溶剂散逸自组装法制备了表面具有特殊形貌的有序多孔膜. 以此多孔膜为模板制备了聚苯胺/聚氨酯（PANI/PU）的凹透镜阵列. 采用红外光谱（FTIR）和扫描电子显微镜（SEM）对界面聚合得到的PANI/PU纳米复合物的结构和凹透镜阵列的形貌进行了表征,研究了不同合成条件对纳米复合物导电性能的影响,并对PANI/PU凹透镜阵列的电学和光学性能进行了研究. 结果表明,PANI/PU凹透镜阵列同时具有导电性、电致收缩性和光衍射性质;其收缩率与外加电压成反比,而透光率与收缩率成正比.     

中空TiO_2微球的制备及对聚丙烯酸酯薄膜性能的影响

采用阳离子聚苯乙烯微球作为模板,钛酸四丁酯为钛源,氨水为催化剂,制备了中空TiO_2微球.采用X射线衍射、扫描电镜及比表面测定仪对其形貌和结构进行了表征,并考察了模板粒径、钛源用量以及催化剂用量对中空TiO_2微球形貌的影响.通过物理共混法将其引入至聚丙烯酸酯乳液中并成膜,研究了复合薄膜的保温性能、抗紫外性能及力学性能.结果表明,锐钛矿相中空TiO_2微球模板粒径、钛源用量以及催化剂用量影响中空TiO_2微球的空心尺寸、壁厚及壳层致密性.中空TiO_2微球可显著提升聚丙烯酸酯薄膜的保温性能、抗紫外性能和力学性能.采用不同粒径的模板制备的中空TiO_2微球对复合薄膜的各项性能均有影响,其中模板粒径为140 nm时复合薄膜性能最优,光反射率提升63%,导热系数降低27%,且在波长小于360 nm范围内,紫外透过率几乎为0,抗张强度增加100%,断裂伸长率提升62%.     

Fabrication of Ordered TiO2 Porous Thin Films by Sol-Dipping PS Template Method

Monolayer polystyrene spheres (∼400 nm) array templates were assembled orderly on clean glass substrates by dip-drawing method from emulsion of PS and porous TiO₂ thin films were prepared by using sol-dipping template method to fill TiO₂ sol into the interstices among the close-packed PS templates and then annealing to remove the PS templates. The effects of TiO₂ precursor sol concentration and dipping time in sol on the porous structure of the thin films were studied. The results showed pore size of the ordered TiO₂ porous thin film depended mainly on PS size and partly on TiO₂ sol concentration. The shrinkage of pore diameter was about 10% for 0.2 M and 20% for 0.4 M TiO₂ sol concentrations. X-ray diffraction (XRD) spectra indicated the porous thin film was anatase structure. The transmittance spectrum showed that optical transmittance of the porous thin film kept above 70% beyond the wavelength of 430 nm. Optical band-gap of the porous TiO₂ thin film (fired at 550^∘;C) was 3.12 eV.     

Template-assisted electrostatic spray deposition as a new route to mesoporous, macroporous, and hierarchically porous oxide films

A novel film coating technique, template-assisted electrostatic spray deposition (TAESD), was developed for the synthesis of porous metal oxide films and tested on TiO(2). Organic templates are codeposited with the titania precursor by electrostatic spray deposition and then removed during calcination. Resultant films are highly porous with pores casted by uniformly sized templates, which introduced a new level of control over the pore morphology for the ESD method. Employing the amphiphilic block copolymer Pluronic P123, PMMA latex spheres, or a combination of the two, mesoporous, macroporous, and hierarchically porous TiO(2) films are obtained. Decoupled from other coating parameters, film thickness can be controlled by deposition time or depositing multiple layers while maintaining the coating's structure and integrity.     

三维有序SiC空心球的制备及表征

以三维有序多孔碳为模板, 以聚甲基硅烷(PMS)为前驱体, 经过前驱体的渗入、交联和陶瓷转化以及多孔碳模板的烧除, 制备了长程三维有序SiC空心球. 所制备的SiC空心球的外径(135-896 nm)、 球壳厚度(14-79 nm)、 BET比表面积(50.8～5.0 m2/g)及微孔体积(0.265～0.038 cm3/g)受不同孔径的多孔碳模板(150-1 000 nm)或不同前驱体浓度的控制. 所制备的SiC空心球以hcp结构排列成长程三维有序的序列.     

分级微纳结构TiO2空心球的制备及其在DSSC中的应用

以钛酸四丁酯为钛源,无水乙醇为溶剂,通过碳球模板法制备出直径为200nm、壳厚20～25nm的TiO2空心球（HS）.通过X射线衍射（XRD）、透射电子显微镜（TEM）、扫描电子显微镜（SEM）和N2吸附脱附等对产物的形貌、晶相组成、孔结构和紫外-可见光谱性质进行了表征,结果显示所制备的锐钛矿相TiO2空心微球是由初级结构纳米级TiO2晶粒构成的.将这种TiO2空心球应用于染料敏化太阳电池（DSSC）领域可以提高光阳极对光的散射.通过制备P25/HS-TiO2双层膜电极,相比单纯的P25纳米晶电极（Jsc=13.5mAcm？2,Voc=0.653V,FF=0.53,η=4.95%）可以得到更高的光电转化效率（Jsc=15.79mAcm？2,Voc=0.653V,FF=0.55,η=6.66%）.     

Ordered porous ZnO thin films formed by dip-coating method using PS templates

Monolayer polystyrene spheres (∼400 nm) array templates were assembled orderly on clean glass substrates by dip-coating method from emulsion of polystyrene (PS). Porous ZnO thin films were also prepared by dip-coating method to fill the interstices among the close-packed PS templates with ZnO and annealing to remove the PS templates. Results showed that ZnO sol concentration and dipping time of PS templates in sol had great influences on the morphology of ordered porous ZnO thin films. There was a shrinkage ratio of about 30% from pore to PS. SEM observation showed that the PS array templates had face-centered cubic close-packing. X-ray diffraction (XRD) spectra showed the porous ZnO thin film was wurtzite structure. The optical transmittance decreased with decreasing wavelength of lights, but was kept above 80% beyond the wavelength of 550 nm. Optical band-gap of the porous ZnO thin film annealed at 500°C was 3.22 eV.     

CNTs/TiO2多孔复合膜的组装及光催化性能

提出了一种在掺氟的SnO2(FTO)导电玻璃上组装碳纳米管(CNTs)/Fe-Ni/TiO2多孔复合膜光催化剂的新方法.采用喷涂热解法(SPD)将掺杂镍和铁的含有嵌段聚合物P123的二氧化钛前驱体溶胶涂覆在FTO导电玻璃上,制备Fe-Ni/TiO2多孔膜,再采用化学气相沉积法(CVD)在Fe-Ni/TiO2膜上原位生长CNTs,得到CNTs/Fe-Ni/TiO2多孔复合膜光催化剂.CNTs/Fe-Ni/TiO2复合膜具有多级孔结构特征,在TiO2表面原位生长的CNTs不但具有较好的石墨化结构,且CNTs较均匀地分布在整个膜层的孔中.考察了CNTs/Fe-Ni/TiO2复合膜光催化剂的结构和性能,并通过降解甲基橙溶液评价了复合膜的光催化活性.结果表明,CNTs的复合及铁和镍的掺杂等改性显著提高了TiO2膜材料的光催化活性.     

Synthesis of porous carbon balls from spherical colloidal crystal templates

Spherical inverse opal (IO) porous carbon was produced utilizing silica colloidal crystal spheres as templates. The spherical colloidal crystals were obtained through the self-assembly of monodisperse particles inside an emulsion droplet with confined geometry. The templates were inverted using a carbon precursor, phenol-formaldehyde (PF) resol. We demonstrated a two-step synthesis involving the subsequent infiltration of the PF resol precursor into the spherical colloidal crystal template and a one-step synthesis using a silica colloidal solution containing dissolved PF resol. In the former case, the sizes of the IO carbon balls were controlled by the size of the colloidal crystal templates, and diameters of a few micrometers up to 50 μm were obtained. The average diameter of the macropores created by the silica particles was 230 nm. Moreover, meso-/macroporous IO carbon balls were created using block-copolymer templates in the PF resol. In the one-step synthesis, the concentration of PF resol in the colloidal solution controlled the diameter of the IO carbon balls. IO balls smaller than 3 μm were obtained from the direct addition of 5% PF resol. The one-step synthesis produced rather irregular porous structures reflecting the less ordered crystallization processes inside the spherical colloidal crystals. Nitrogen adsorption and cyclic voltammetry measurements were conducted to measure the specific area and electroactive surface area of the IO carbon balls. The specific area of the mesopores-incorporated IO carbon balls was 1.3 times higher than that of bare IO carbon balls. Accordingly, the meso-/macroporous porous carbon balls exhibited higher electrocatalytic properties than the macroporous carbon balls.     

Preparation and Photocatalytic Property of Porous TiO_2 Film with Net-like Framework

By the UV-curing method, a porous TiO2 film with net-like framework has been prepared. The characte-rization results of the porous TiO2 film by means of SEM, TEM, XRD, and N2 adsorption-desorption analysis show that the net-like framework of the porous TiO2 film is composed of TiO2 nanoparticles, forming three dimensional porous structure. The porous TiO2 film exhibits higher photocatalytic activity for the degradation of methylene blue(MB) dye compared with the conventional dense TiO2 film.