VO_2-WO_3复合薄膜的制备及其热致变色-电致变色性能研究

智能玻璃是目前建筑节能重点研究方向。本研究将自制氧化钒纳米粉体均匀分散到钨溶胶体系,取上清液旋涂于ITO基板,经干燥、退火后制得VO_2(M)-非晶WO_3复合薄膜。实验结果表明,所制备的VO_2(M)-非晶WO_3复合薄膜兼具热致变色和电致变色性能,通电后薄膜表现典型的电致变色特征,可见光和近红外光透过率明显下降。退火过程中,部分W掺杂到VO_2中,使薄膜的热致相变温度降低10°C左右。复合薄膜在双响应条件下,其可见光透过率为32.6%、调控效率为18.8%。     

La3+掺杂TiO2薄膜制备及其电致变色特性研究

基于提高TiO2薄膜的光学属性和着色效率,以钛酸四丁酯和氧化镧为主要原料,采用溶胶-凝胶法,在ITO玻璃表面制备La3+掺杂TiO2薄膜.通过XRD、SEM、EDS、TG-DTA等手段对制备La3+掺杂TiO2凝胶粉末进行表征,使用电化学工作站CHI660E和紫外-可见光分光光度计UV-5500PC对La3+掺杂TiO2薄膜的电致变色性能进行测试.结果表明:凝胶在加热的过程中发生一系列的物理和化学反应,且当温度升高至400 ℃时,系统达到相对热稳定状态.经600℃热处理,La3+掺杂TiO2转化为金红石相.外加电压为-2V时,薄膜显示为深蓝色,反向施压至+2V时,蓝色褪去.金红石相TiO2无定形程度随La3+掺入量增加而提高,对应其着色效率提高.La3掺杂TiO2薄膜在可见光范围内透过率均在70％ ～ 80％,光学性能良好.     

Au/TiO2-B催化剂的CO低温氧化性能

探索Au纳米粒子对新型材料的催化性能可以显著拓宽金催化剂的应用范围。使用TiO₂-B作为载体,担载Au纳米粒子并应用于低温CO氧化反应体系。TiO₂-B为长度5～20 mm的微米级纤维,Au纳米粒子粒径在3 nm以下,均匀地分散在TiO₂-B表面。CO 氧化测试表明,Au纳米粒子的性能受TiO₂-B焙烧温度的影响,不同焙烧温度会引起Au分散性以及Au纳米粒子与载体相互作用的改变。分散于纯TiO₂-B载体上的金的催化活性可与其分散在锐钛矿纳米粉体上的相媲美。此外,300℃下活化的Au纳米粒子表现出了最佳的CO氧化性能,在氧化性气氛中活化的催化剂的催化性能优于在惰性和还原性气氛中活化的催化剂。     

浅析电致变色玻璃中的电致变色材料

介绍了电致变色玻璃的结构、工作原理及特性。电致变色材料是电致变色玻璃的核心部分,着重分析了其不同的种类、性能特点及反应原理。     

氧化石墨烯及其负载TiO2复合材料的制备和表征

研究采用传统Hummers法制备GO(1)和改进Hummers法制备GO(2),并对它们进行SEM、XRD、FTIR表征.结果表明:GO(2)比GO(1)更加的蓬松,在水中分散度更高;GO(2)的氧化程度更高.GO(2)的晶面间距0.80 nm,GO(1)的晶面间距0.75 nm,两者均远大于石墨原料的0.34 nm....     

电致变色薄膜研究进展

本文概述了电致变色薄膜材料、变色机理、工作原理等方面的研究进展,并探讨了目前存在问题的解决途径。     

溶胶—凝胶法制备TiO2—CeO2电致变色离子贮存层的性能

采用钛本丁酯和硝酸亚铈为前驱物制备出性能较好、可用于电致变色装置的离子贮存电极材料,分析了薄膜材料制备条件对其电化学性能的影响。结果表明该材料克隆了纯氧化铈材料对电化学响应速率低的不足,具有可逆的电化学离子注入及在可见光范围内保持透明的特性。     

有机硅改性聚甲基丙烯酸甲酯一聚苯胺复合材料的制备及其电致变色性能研究

本文采用溶液聚合法及乳液聚合法合成了可溶性聚苯胺,用光电子能谱、X－射线衍射对其本征态及掺杂态的结构进行了表征。以甲基丙烯酸甲酯－甲基丙烯酰丙基三甲氧基硅烷共聚物为基体,用溶液复合法制备了聚苯胺复合电致变色膜,并采用扫描电镜、循环伏安法等对其结构和电致变色性能进行研究。结果表明复合电致变色膜在稳定态时仅出现第二氧化峰,在外加电压作用下其颜色在绿色至蓝黑色之间可逆变化。共聚物中含有偶联剂组分可以提高电致变色膜与ITO导电玻璃基底的粘结性及改善复合电致变色薄膜的耐溶剂性能。     

TiO_2/氧化石墨烯复合催化剂的制备及其光催化性能研究

采用改进的Hummers法制备氧化石墨烯,在此基础上以该GO为载体,通过浸渍-沉淀法在其表面合成TiO2纳米粒子,再通过450℃的焙烧形成TiO2/GO二元复合光催化剂,研究复合光催化剂在紫外光下降解甲基橙的动力学及活性变化规律。使用透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)和紫外可见漫反射光谱等分析了复合光催化剂的形貌、TiO2粒子的结晶状态以及催化剂的光吸收。结合光催化降解甲基橙实验,探索了复合光催化剂中TiO2含量对其光催化活性的影响。研究结果表明,在TiO2质量分数低于20%时,复合光催化剂中TiO2均匀分散于GO表面;质量分数超过20%复合催化剂中将会有少量TiO2团聚体出现。由于氧化石墨烯的协同效应,紫外光下TiO2/GO复合催化剂的光催化活性要远高于TiO2光催化剂。     

普鲁士蓝基电致变色薄膜制备及性能的研究进展

讨论了普鲁士蓝(PB)的电致变色机制,总结了近年来国内外学者为提高其电致变色性能进行的研究.概述了目前制备PB薄膜的主要方法及其工艺与性能的关系,陈述了PB与其他材料复合对电致变色器件性能改善的机理.说明了缩短离子扩散距离、增大与离子层接触面积及改善基底导电性是提高PB电致变色器件性能的重要方法.最后提出PB电致变色器...     

Preparation and properties of bacterial cellulose/graphene oxide composite films using dyeing method

In this study, bacterial cellulose (BC) hydrogels were cultured from a kombucha SCOBY starter. The scanning electron microscopy (SEM) results indicated that the dried BC exhibited an interpenetrating fibrous mat. The BC films harvested for 5, 10, and 15 days were 15–19, 14.4–24, and 30–31 μm thick, respectively. Then, BC/graphene oxide (GO) composite films were prepared via the exhaust dyeing method. GO sheets penetrated the BC matrix, resulting in the formation of a BC/GO composite, as revealed by the SEM analysis results. The mechanical properties of the composite films were investigated. Compared with virgin BC, the tensile strength of the composite films was higher, while the %E at break was lower, resulting in a significant increase in the Young's modulus. The X-ray diffraction results indicated that an increase in the dyeing time (0.5–2 h) gradually induced cellulose crystalline conformation, which in turn affected the swelling ability, mechanical properties, and electrical properties of the BC/GO composite films. After the reduction of GO to reduced GO (rGO), flexible conductive BC/rGO films were obtained, as confirmed by their resistivity values. Thus, flexible conductive composite films with excellent mechanical properties were successfully fabricated.     

二氧化钛/氧化石墨烯复合光催化剂的合成

采用水热法,以钛酸四正丁酯及氧化石墨烯（GO）为原料,在水性体系中合成了一系列具有不同GO质量分数的TiO2/GO复合光催化剂。FE-SEM分析结果表明,分散的钛酸四正丁酯以多分子层的形式吸附到氧化石墨烯的表面,最后在水热过程中转化为锐钛型TiO2粒子。当氧化石墨烯的质量分数低于3%时,产物中含有纯TiO2微球及TiO2/GO复合物;当氧化石墨烯质量分数大于5%时,产物为单纯的TiO2/GO复合物。电化学性能测试结果表明,GO复合后,TiO2电极中载流子的传输效率提高。氧化石墨烯复合量为10%时,复合光催化剂显示了对亚甲基蓝最佳的光催化活性。当复合氧化石墨烯转化为石墨烯后,其光催化活性可得到进一步大幅度的提高。     

Preparation and lithium storage properties of Mo2N quantum dots@nitrogen-doped graphene composite

To improve the electrochemical lithium storage performance of molybdenum nitrides, Mo₂N quantum dots@nitrogen-doped graphene oxide sponge (Mo₂N-QDs@Ngs) was prepared by hydrothermal reaction, freeze-drying and calcination in H₂/N₂ mixture with ammonium molybdate ((NH₄)Mo₇O₂₄·4H₂O), hexamethylenetetramine (C₆H₁₂N₄) and graphene oxide (GO) as raw materials. The effect of GO content on the electrochemical lithium storage performance was investigated. The transmission electron microscope (TEM) results show that the size of the prepared Mo₂N quantum dots is about 2—5 nm, and the Mo₂N quantum dots are uniformly distributed on the surface of nitrogen-doped graphene. The electrochemical test results show that when the GO content is 30%, the prepared Mo₂N-QDs@Ngs-30 has the best electrochemical lithium storage performance, which has 699 mA·h·g^-1 specific capacity at the current density of 0.1 A·g^-1, and has 286 mA·h·g^-1 specific capacity even at the current density of 2 A·g^-1.     

Mo2N量子点@N-掺杂石墨烯复合材料的制备及储锂性能

为改善钼氮化物的电化学储锂性能,以钼酸铵、六次甲基四胺及氧化石墨烯（GO）为原料,通过水热、冷冻干燥及在H₂/N₂混合气中热处理,制备了Mo₂N量子点@氮掺杂石墨烯复合材料（Mo₂N-QDs@Ngs）,并探究了GO复合量对电化学储锂性能的影响。透射电子显微镜（TEM）测试结果表明：制备的Mo₂N量子点尺寸约为2~5 nm,Mo₂N量子点均匀地分布在氮掺杂石墨烯的表面。电化学测试结果表明：当GO复合量为30%时（Mo₂N-QDs@Ngs-30）,制备的复合材料具有最佳的电化学储锂性能,其在0.1 A·g^-1的电流密度下具有699 mA·h·g^-1的比容量,在2 A·g^-1下仍具有286 mA·h·g^-1的比容量。     

石墨烯基TiO_2光催化剂的制备及其研究进展

石墨烯作为一种新型二维碳质纳米材料,与TiO_2复合可制得石墨烯基TiO_2光催化材料。介绍了石墨烯的结构与性质,概述了石墨烯及石墨烯基TiO_2光催化剂的制备方法,并总结了石墨烯基TiO_2复合材料在光催化分解水制氢、光催化还原CO_2、光催化降解有机污染物等领域的应用及未来的发展方向。     

Synergistic enhancement of polyvinylpyrrolidone-modified TiO2 and graphene oxide on the corrosion resistance of waterborne epoxy

Waterborne epoxy (WEP) resins have garnered significant interest due to their potential application as anticorrosion coatings for steel materials. However, it has been reported that defects in the cured coatings generated during the curing process lead to the level of anticorrosion not meeting the expected effects. In this study, TiO₂ and GO were selected to be modified by polyvinylpyrrolidone (PVP) to obtain PT and PG, and used to improve the anticorrosion performance of WEP. The obtained PT and PG were characterized using Fourier transform infrared, Raman, and x-ray photoelectron spectroscopy. The morphology of PT and PG before and after modification was observed using scanning electron microscopy, and the differences were described. The analysis results of laser confocal scanning microscopy and water contact angle (WCA) indicate that there are differences in surface roughness and WCA of the WEP coatings with or without PT and PG. Electrochemical impedance spectroscopy was used to evaluate the anticorrosion performance of the coatings. The results showed that WEP coatings containing PT and PG exhibited better anticorrosion performance. The synergistic enhancement of PT and PG on the anticorrosion performance was proposed, which can be attributed to the comprehensive effect of the hydrophobicity of the coating surface and the barrier effect of PT and PG within the coatings.     

Preparation of polyimide/siloxane‐functionalized graphene oxide composite films with high mechanical properties and thermal stability via in situ polymerization

An effective approach to prepare polyimide/siloxane‐functionalized graphene oxide composite films is reported. The siloxane‐functionalized graphene oxide was obtained by treating graphene oxide (GO) with 1,3‐bis(3‐aminopropyl)‐1,1,3,3‐tetra‐methyldisiloxane (DSX) to obtain DSX‐GO nanosheets, which provided a starting platform for in situ fabrication of the composites by grafting polyimide (PI) chains at the reactive sites of functional DSX‐GO nanosheets. DSX‐GO bonded with the PI matrix through amide linkage to form PI‐DSX‐GO films, in which DSX‐GO exhibited excellent dispersibility and compatibility. It is demonstrated that the obvious reinforcing effect of GO to PI in mechanical properties and thermal stability for PI‐DSX‐GO is obtained. The tensile strength of a composite film containing 1.0 wt% DSX‐GO was 2.8 times greater than that of neat PI films, and Young's modulus was 6.3 times than that of neat PI films. Furthermore, the decomposition temperature of the composite for 5% weight loss was approximately 30 °C higher than that of neat PI films. © 2015 Society of Chemical Industry     

静电纺丝法制备氧化钛-氧化石墨复合载体的加氢脱硫性能

以静电纺丝法制备TiO₂纳米纤维(TiO₂(NF))和TiO₂-氧化石墨(GO)复合纳米纤维(TiO₂(NF)-GO)加氢脱硫催化剂的载体,采用等体积浸渍法制备NiMo/TiO₂(NF)和NiMo/TiO₂(NF)-GO催化剂,运用N₂吸附-脱附、X射线衍射、XPS、TEM、Raman光谱和NH₃程序升温脱附等表征手段对载体和催化剂进行表征分析,并考察掺杂不同含量GO对催化剂加氢脱硫性能的影响。实验结果表明,当GO/TiO₂(NF) 质量分数为0.5%时,复合载体的中强酸增加得最多,在温度280℃、氢气分压2.0 MPa、体积空速4 h^-1,氢油体积比400相当温和条件下,对应的催化剂表现出优异的加氢脱硫性能。     

氧化石墨烯杂化分子印迹复合膜制备及性能研究

采用改进的Hummers法,通过冷冻干燥制备了氧化石墨烯(GO)。以辛弗林盐酸盐为模板分子,水溶性的丙烯酰胺为功能单体,离子液体(溴代1-丁基-3-甲基咪唑)为致孔剂,把GO加入聚合液中,制备了GO杂化的分子印迹复合膜(GO-MIM)。利用透射电镜、扫描电镜、X射线衍射和红外光谱等方法对GO及GO-MIM进行了表征。通过将分子印迹膜技术与GO相结合,明显提高了分子印迹膜的力学性能。吸附及渗透实验表明,GO-MIM可在纯水溶剂体系,对辛弗林盐酸盐具有很好的选择性吸附能力和优先透过能力,体现了明显的分子印迹效果。