凝胶网格沉淀法制备纳米氧化锌及其性能研究

以明胶为原料用凝胶网格沉淀法制备了纳米ZnO和铝掺杂纳米ZnO粉体,探讨其最佳制备条件,当反应温度为85℃、明胶浓度为10%时凝胶强度最适宜。利用XRD、TEM等方法对纳米粉体结构和粒径进行表征,并进行ζ-电位分析和气敏性测试。XRD测试结果表明粒子为六方晶系结构,XRD和TEM测试结果表明该粒子的平均粒径在25 nm左右。通过ζ-电位测定表明ZnO等电点在8.0~8.5之间,铝掺杂ZnO的等电点为7.5~8.0之间。气敏性测试表明铝掺杂的氧化锌对三甲胺(TMA)气体敏感,灵敏度达3.0以上,且敏感性与掺杂量有关。     

ZnO-PFD纳米复合材料的制备及其光催化性能

以糠醛和ZnO粉体为原料,用酸催化聚合的方法制备了复合光催化剂前驱体,经适当热处理后得到ZnO-共轭高分子(ZnO-PFD)纳米复合微粒,通过SEM、XRD、FTIR、UV-vis、TG-DTA等技术对其表面形貌及结构进行了表征。结果表明,复合微粒的粒径为50～100nm,其中ZnO呈六方纤锌矿结构,PFD的掺杂拓宽了ZnO的光谱响应范围,使其能吸收紫外-可见区的全程光波。在自然光、室温条件下,以亚甲基蓝(MB)的脱色降解为模型反应,考察了复合微粒的光催化性能,探讨了热处理温度和ZnO含量对复合微粒光催化性能的影响。当热处理温度为400℃,ZnO的质量分数为48.62%时,复合微粒对MB降解反应20min,就可使MB水溶液完全脱色,COD去除率达70.24%,ZnO重复使用3次后,对MB的脱色率仍可达87%。     

纳米塑料性能优异

纳米塑料是指无机填充物以纳米尺寸分散在有机聚合物基体中形成的有机／无机纳米复合材料。纳米塑料具有一般工程塑料所不具备的优异性能,因此是一种高科技的新材料,具有广泛的开发和应用前景。     

纳米肤色氧化锌的制备新工艺研究

报道了以碳酸铵为沉淀剂 ,在洗涤过程中使用有机溶剂 ,制得纳米肤色ZnO的新方法。对产品进行了化学分析、XRD、TEM等检测。结果表明 ,用该法合成的ZnO具有六方晶系结构 ,呈肤色 ,类球形 ,分散性好 ,粒径介于 10— 2 0mm之间。该产品可用于化妆品、医药、颜料、塑料等领域。     

氧化锌纳米晶的制备及光催化性能研究

采用沉淀-热分解方法制备纳米ZnO,并用场发射扫描电子显微镜和X-射线衍射仪分析所制备的ZnO粉体的晶粒大小和物相,同时研究了在不同煅烧温度下制备的纳米ZnO对次甲基蓝的光催化降解效率.实验结果表明:在450 ℃下煅烧2 h制备的ZnO粉体的粒径基本分布在20～40 nm的范围内,且具有(假)六方结构.将在400 ℃和500 ℃下合成的ZnO纳米晶相比,在450 ℃下合成的样品对次甲基蓝的光催化降解效率较高;此外,外加适量的30%H2O2(质量含量,下同)溶液能显著提高纳米ZnO对次甲基蓝的光催化降解效率.     

纳米氧化锌的制备方法及其光催化性能

纳米氧化锌（ZnO）作为一种高功能材料,被广泛应用于气体传感、催化、能源、光电材料等领域,在紫外光照射下,可产生光致电子-空穴对,表现出良好的光催化特性,可以提高氧化还原反应的速率,氧化难降解有机物用于污染治理,具有无毒、高效、低成本等优点。综述了近年来纳米氧化锌的制备方法及原理,介绍了其光催化性能的机理和表征方法。提出今后需加强对掺杂纳米ZnO的理论和制备技术研究,加大纳米ZnO薄膜光催化性能的研究,对纳米ZnO进行改性,提高光催化活性,进一步拓宽工业化应用领域。     

片状纳米氧化锌的制备及其光学性能的研究

采用三种不同前驱体,以三聚磷酸钠为表面改性剂,水热法制备了少有报导的片状纳米ZnO,采用X-射线衍射仪、透射电镜、荧光光谱仪及紫外可见分光光度计等手段对所得粉末进行表征.结果表明:当pH值为9-10,180℃水热反应一定时间,三种前驱体均可制得片状结构znO晶体,片状ZnO晶体(001)晶面衍射峰最强,具有明显的择优性,这与其它形态的ZnO有所不同;以碱式硫酸锌为前驱体时,可获得具有良好紫外吸收性能,并在421 nm附近具有单一较强蓝光发光峰的ZnO粉;而以碱式氯化锌、碱式硝酸锌等为前驱体时ZnO则具有383nm附近的紫外发光和571nm左右的黄绿色发光.     

提拉法制备氧化锌纳米颗粒电极及其耐腐蚀性能

利用提拉法在紫铜基体上制备了ZnO涂层,并研究了成膜添加剂及水热加强过程对其机械性能及耐腐蚀性能的影响.研究表明,在ZnO溶胶液中加入成膜添加剂可使ZnO涂层形成大量直径为300 nm左右的孔洞,大幅提高了涂层的比表面积、附着力、硬度和耐磨性能;进一步的水热处理过程可在纳米多孔ZnO涂层之上生长一层粒径为100 nm左...     

ZnO纳米纤维制备及其性能表征

以PVP为前驱体溶液,采用静电纺丝法制备了PVP/Zn(CH3COO)2复合纤维,通过煅烧进一步制得了ZnO纳米纤维。并对所得样品进行了扫描电子显微镜(SEM)分析,TG-DTG分析,并对纳米ZnO纤维和纳米ZnO颗粒的抗菌性能进行了测试。     

ZnO纳米纤维制备及其性能表征

以PVP为前驱体溶液,采用静电纺丝法制备了PVP/Zn(CH3COO)2复合纤维,通过煅烧进一步制得了ZnO纳米纤维。并对所得样品进行了扫描电子显微镜(SEM)分析,TG-DTG分析,并对纳米ZnO纤维和纳米ZnO颗粒的抗菌性能进行了测试。     

Structure and photovoltaic properties of ZnO nanowire for dye-sensitized solar cells

Aligned ZnO nanowires with different lengths (1 to approximately 4 μm) have been deposited on indium titanium oxide-coated glass substrates by using the solution phase deposition method for application as a work electrode in dye-sensitized solar cells (DSSC). From the results, the increases in length of zinc oxide (ZnO) nanowires can increase adsorption of the N3 dye through ZnO nanowires to improve the short-circuit photocurrent (J_sc) and open-circuit voltage (V_oc), respectively. However, the J_sc and V_oc values of DSSC with ZnO nanowires length of 4.0 μm (4.8 mA/cm² and 0.58 V) are smaller than those of DSSC with ZnO nanowires length of 3.0 μm (5.6 mA/cm² and 0.62 V). It could be due to the increased length of ZnO nanowires also resulted in a decrease in the transmittance of ZnO nanowires thus reducing the incident light intensity on the N3 dye. Optimum power conversion efficiency (η) of 1.49% was obtained in a DSSC with the ZnO nanowires length of 3 μm.     

Solid-state dye-sensitized solar cells based on ZnO nanoparticle and nanorod array hybrid photoanodes

The effect of ZnO photoanode morphology on the performance of solid-state dye-sensitized solar cells (DSSCs) is reported. Four different structures of dye-loaded ZnO layers have been fabricated in conjunction with poly(3-hexylthiophene). A significant improvement in device efficiency with ZnO nanorod arrays as photoanodes has been achieved by filling the interstitial voids of the nanorod arrays with ZnO nanoparticles. The overall power conversion efficiency increases from 0.13% for a nanorod-only device to 0.34% for a device with combined nanoparticles and nanorod arrays. The higher device efficiency in solid-state DSSCs with hybrid nanorod/nanoparticle photoanodes is originated from both large surface area provided by nanoparticles for dye adsorption and efficient charge transport provided by the nanorod arrays to reduce the recombinations of photogenerated carriers.     

聚氨酯-丙烯酸酯复合乳液的合成与性能

采用甲基丙烯酸甲酯(MMA)与水性聚氨酯乳液共聚反应制备聚氨酯-丙烯酸酯(PUA)复合乳液,研究了MMA添加量、引发剂种类和聚合温度对PUA复合乳液及涂膜性能的影响,确定了PUA复合乳液合成的工艺参数。用傅立叶红外光谱(FTIR)测定反应产物的结构。研究发现油溶性引发剂比水溶性引发剂更适合PUA体系的乳液聚合。随着MMA添加量的增大,PUA复合乳液胶粒粒径增大,黏度减小,涂膜光泽度下降,机械性能增强,耐水性增加。     

电沉积纳米材料性能及应用的最新研究进展

电沉积纳米材料的制备工艺已经被人们所熟悉,它简单的制备工艺和低廉的价格吸引了各个领域的研究人员。本文对电沉积纳米材料的性能进行了总结,并列举出了目前的应用实例。     

有机/无机杂化光伏电池

介绍了有机/无机杂化光伏电池的工作原理,对无机半导体的种类及杂化方式作了简单介绍,同时叙述了几种用于制备杂化光伏电池的聚合物的设计合成及有机/无机杂化光伏电池的研究现状,最后指出了目前制备有机/无机杂化光伏电池所存在的问题.     

Effect of Al doped ZnO on optical and photovoltaic properties of the p-Cu2O/n-AZO solar cells

Metal oxide thin films have fared so well in the semiconductor industry because of their superior physical, electrical, and optical properties. The applications of these materials in solar cells, biosensors, biomedicine, supercapacitors, photocatalysis, luminous materials, and laser systems are becoming increasingly popular. In this study, the influence of Al concentration on Cu₂O/AZO heterojunction thin films was examined systematically. First, arrays of n-ZnO and AZO rods were produced on an ITO substrate using a hydrothermal technique at 140 °C. Then, using an alkaline cupric lactate solution, a thin films of p-Cu₂O were electrodeposited at 60 °C onto the ZnO arrays. The structure and morphology of the produced materials and the solar cells were studied using X-ray diffraction and scanning electron microscopy. The optical measurements demonstrate a shift in the absorption edge with increasing Al content. Solar cells have been created with a device structure of ITO/ZnO/Cu₂O/Al and ITO/Al-doped ZnO/Cu₂O/Al configurations. The power conversion efficiency (?) of the inorganic solar cell with 6% Al-doped ZnO is ? = 0.282%, which is greater than the ? of the ZnO-based solar cell (? = 0.17%).     

影响染料敏化二氧化钛纳米晶太阳能电池的因素

介绍了染料敏化二氧化钛纳米晶太阳能电池的结构及工作原理,对影响染料敏化太阳能电池性能的因素,如纳米二氧化钛膜的制备、表面修饰、耦合及掺杂或复合,敏化染料与电极表面的吸附、吸收光谱与太阳光谱的匹配、染料的设计合成,以及电解质的研究进展进行了综述。指出染料和电解质的性能是今后发展中的主要制约因素,纳米多孔膜的制备、染料的光电化学反应机理和染料的设计合成、双敏化、固态空穴传输材料替代液体电解质以及纳晶多孔电极与染料间能量传递及电子转移的微观本质等领域是今后的主要研究方向。     

ZnO photoanodes with different morphologies grown by electrochemical deposition and their dye-sensitized solar cell properties

In this article, we grew zinc oxide (ZnO) samples with different morphologies, e.g. film, nanowire and nanosheet, with electrochemical deposition (ECD) by controlling the precursor concentration and the growth mechanism was also discussed. The morphology influence on the photovoltaic conversion efficiency of the dye-sensitized solar cells (DSSC) assembled with different ZnO photoanodes was investigated by measuring current density–voltage (J–V) curve, quantum efficiency (QE) spectrum and electrochemical impedance spectrum (EIS). It was found that the DSSC constructed with ZnO nanowire array as photoanode can absorb more dye, improve the photon utilization rate and provide rapid collection channels for the photoexcited carriers. Therefore, the photovoltaic conversion efficiency of ZnO nanowire DSSC was improved.     

Rapid synthesis and dye-sensitized solar cell applications of hexagonal-shaped ZnO nanorods

This paper reports, for the first time, a very rapid and large-scale synthesis and dye-sensitized solar cells (DSSCs) application of well-crystallized hexagonal-shaped ZnO nanorods at very low temperature of about 70 °C in 20 min. The thin films of as-grown nanorods were used as photo-anode materials to fabricate the DSSCs which exhibited an overall light to electricity conversion efficiency (ECE) of 1.86% with a fill factor of 74.4%, short-circuit current of 3.41 mA/cm² and open-circuit voltage of 0.73 V.     

CdSe nanocrystal sensitized ZnO core-shell nanorod array films: Preparation and photovoltaic properties

ZnO/CdSe core-shell nanorod array films were synthesized via a two-step method. ZnO nanorod array films were first grown on a TCO substrate, and then CdSe nanocrystals were deposited on the nanorods to form core-shell structured films. The resulting films were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis absorption spectroscopy. Especially, dark-field images and transmission electron diffraction of the TEM were used to study the morphology and the chemical nanostructure of the ZnO/CdSe core-shell nanorods in detail. We investigated the photovoltaic performance of the resulting ZnO/CdSe core-shell nanorod array films as solar cell photoanodes. Parameters, such as the length of the ZnO nanorods, the shell phase structure and the deposition time of the CdSe nanocrystals were found to affect the photovoltaic performance of the solar cell. This study provides a facile method to prepare nanocomposite photoanodes of solar cells, and gives some insight about the fundamental mechanisms that improve the performance.