功能化纳米晶与聚醚的分子组装

以醋酸镉和硫脲为原料,巯基乙醇为有机配体,制备了粒径可控的,表面富有羟基的CdS纳米晶.表面的羟基与γ-(2,3-环氧丙氧)丙基三甲基硅烷发生缩合反应,得到功能化的CdS纳米晶粉末在双金属催化剂的存在下,与环氧丙烷进行开环聚合,制备出分子组装的CdS纳米晶/聚醚接枝共聚物.用TEM表征了CdS纳米晶的形貌,紫外-可见光吸收光谱测定了纳米晶的光学性能,FT-IR证实了有机物在纳米晶表面的接枝.     

功能化CdS纳米晶的制备

以氯化镉和硫化钠为原料,2-巯基乙醇(ME)为有机配体,成功制备了粒径可控的、表面富有羟基的CdS纳米晶.采用不同的ME/Cd2 及H2O/DMF比例以观察有机配体及溶剂对生成粒子尺寸的影响.透射电子显微图证实了球形CdS纳米粒子很好地分散在H2O/DMF溶液中,没有任何团聚现象发生.傅立叶变换红外谱图(FT-IR)显示了羟基基团成功地包覆在纳米晶的表面.X线衍射(XRD)测试揭示了功能化CdS纳米晶的晶形主要为立方晶.     

水溶性发光硫化镉纳米晶的制备

以氯化镉和硫化钠为原料,巯基乙酸为有机配体,水为溶剂,制得表面羧基化的CdS纳米晶。利用FTIR、XRD、UV-vis、荧光光谱(PL)考察了CdS纳米晶的结构与性能。结果表明,羧基基团包覆在纳米晶表面,所制得的CdS纳米晶以立方晶型为主,电子-空穴对复合引起的表面发射和硫空位引起的缺陷发射共同作用,使得CdS纳米晶在紫外光照射下发出明显的黄光,表现出良好的光致发光性能。     

复合结构纳米晶CdS：Cu/CdS的制备及光学特性

在非配位溶剂中合成了高质量的CdS纳米晶核,并利用Cu2+离子对其进行掺杂,制备了CdS:Cu纳米晶.通过进一步采用连续离子层吸附反应的方法对CdS:Cu纳米晶进行表面修饰,得到CdS:Cu/CdS复合结构纳米晶.利用X射线衍射(XRD),透射电镜(TEM),紫外可见吸收光谱(UV-Vis)和荧光光谱(PL)对其结构、形貌以及光学性质进行了表征和分析,结果表明:所制备的复合结构CdS:Cu/CdS纳米晶为立方闪锌矿结构;与CdS纳米晶核相比,掺杂Cu2+可以使其表面态发光发生红移;在CdS:Cu纳米晶中,通过改变掺杂Cu2+的浓度,可以实现表面态发光在570和620nm之间的连续调节.与未经包覆的CdS:Cu纳米晶相比,包覆层CdS增强了纳米晶CdS:Cu的稳定性.     

复合结构纳米晶CdS∶Cu/CdS的制备及光学特性

在非配位溶剂中合成了高质量的CdS纳米晶核,并利用Cu²⁺离子对其进行掺杂,制备了CdS∶Cu纳米晶.通过进一步采用连续离子层吸附反应的方法对CdS∶Cu纳米晶进行表面修饰,得到CdS∶Cu/CdS复合结构纳米晶.利用X射线衍射(XRD),透射电镜(TEM),紫外可见吸收光谱(UV-Vis)和荧光光谱(PL)对其结构、形貌以及光学性质进行了表征和分析,结果表明:所制备的复合结构CdS∶Cu/CdS纳米晶为立方闪锌矿结构;与CdS纳米晶核相比,掺杂Cu²⁺可以使其表面态发光发生红移;在CdS∶Cu纳米晶中,通过改变掺杂Cu²⁺的浓度,可以实现表面态发光在570和620nm之间的连续调节.与未经包覆的CdS∶Cu纳米晶相比,包覆层CdS增强了纳米晶CdS∶Cu的稳定性.     

纳米CdS材料的研究与应用进展

综述了近年来纳米CdS的制备技术及其材料的研究与应用进展,认为纳米CdS高分子材料具有含量可控、稳定性好、表面可修饰、光学性能好等优点,在光、电、传感、催化等领域有良好的发展前景,有待于深入研究.     

P3HT/Fe_3O_4/CdS磁性纳米复合材料的制备及其三阶NLO性能

聚噻吩衍生物/纳米半导体复合材料由于协同了有机、无机材料的优势,具有显著的三阶非线性光学(NLO)性质。采用原位复合法制备磁性聚(3-已基噻吩)-Fe_3O_4/CdS(P3HT-Fe_3O_4/CdS)纳米复合物。采用傅里叶红外光谱(FT-IR)、X射线衍射(XRD)、透射电镜(TEM)、扫描电镜(SEM-EDAX)和激光散射法粒度测试仪(HPPS)等方法对产物进行了表征。结果表明,P3HT-Fe_3O_4/CdS具有良好的顺磁性,其中的Fe_3O_4和CdS的粒径约为2~4nm。分别用紫外可见(UV-Vis)、荧光光谱(PL)和Z-扫描方法检测复合材料的光学性质。P3HTFe_3O_4/CdS的n~2约为1.36×10~(-9) esu,χ(3)约为9.76×10~(-12) m~2/W,具有良好的三阶NLO性质。该磁性纳米复合材料有助于在磁场、电场中构建有序微纳结构,在光电磁复合材料领域具有潜在的应用价值。     

原位法P3HT-COOH/CdS纳米复合材料的制备与表征

以二水乙酸镉(Cd(OOCCH3)2·2H2O)为镉源,硫粉(S)为硫源,二氯苯(DCB)和二甲基亚砜(DMSO)为混合溶剂,末端羧基化聚-3-己基噻吩(P3HT-COOH)为模板,原位法合成了P3HT-COOH/CdS纳米复合材料;并利用核磁共振氢谱、傅里叶变换红外光谱、X射线衍射、透射电子显微镜、紫外-可见光谱和荧光光谱等分析测试方法对其组成、形貌、光电性能等进行了表征。研究了不同反应温度及S/Cd摩尔比对复合材料形貌及光电性能的影响。实验结果表明,所合成的CdS纳米粒子均匀分布在P3HT-COOH/CdS复合材料中;CdS的尺寸和分布不仅受温度影响,还很大程度上受S/Cd摩尔比的影响;P3HT-COOH/CdS纳米复合材料有较强的荧光淬灭,表明CdS与P3HT-COOH之间有电荷转移。     

P(S-SS)/CdS核壳粒子的制备与表征

采用超声辐照乳液聚合得到聚(苯乙烯-苯乙烯磺酸钠)(P(S-SS))乳胶粒,用直接沉淀法在乳胶粒表面原位生成硫化镉(CdS)纳米粒子,得到P(S-SS)/CdS核壳粒子。用元素分析和XPS研究了共聚物的组成及磺酸基(-SO3-)的分布,结果表明,-SO3-主要分布在乳胶粒表面,有利于CdS纳米粒子在乳胶粒表面的沉积。用XRD、TEM及UV-v is表征了共聚物乳胶粒及P(S-SS)/CdS核壳粒子的结构及CdS的量子效应。结果表明,所制备的CdS纳米粒子为六方晶型,平均粒径为6 nm,在P(S-SS)乳胶粒外层形成多层包覆,P(S-SS)/CdS核壳粒子平均粒径为70 nm,CdS纳米粒子表现出明显的量子尺寸效应。     

纳米纤维素/CdS纳米复合光电材料的制备和性能

以NaClO2为主要氧化剂,使用氧化漂白桉木浆制备C-6位羧基含量为0.8mmol/g的TEMPO氧化纤维素,然后将其剪切为纳米纤维素(NCC)。再以NCC为基材,以无水氯化镉及硫化钠为前驱体,用声化学法制备了NCC/CdS纳米复合光电材料。用X射线衍射(XRD)、场发射扫描电镜(SEM)、傅里叶红外光谱仪(FT-IR)以及光电化学实验对复合材料的结构及性能进行表征。结果表明,大量CdS纳米粒子复合在NCC基材上形成NCC/CdS纳米复合材料,CdS晶粒为立方型晶体,大小为7.3nm。用NCC/CdS纳米复合材料形成的薄膜器件在可见光区域的透光率高达60%。这种复合材料可产生1.35μA的光电流,其光电转换效率为微晶纤维素/CdS复合材料的6倍。     

CdS及其稀土掺杂纳米带的制备与发光性质的研究

采用热蒸发法制备CdS及其稀土掺杂的纳米带(CdS∶Ce3+、CdS∶Er3+)。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)和荧光光谱仪(PL)对纳米带的形貌、晶体结构和发光性质进行了表征和分析。结果表明,所制备的纳米带的外形规则,表面光滑、平整,纳米带的厚度大约在20～60nm范围内;纳米带具有六方结构,晶格常数a=0.414nm、c=0.671nm;CdS纳米带的光致发光谱的谱峰位于405nm左右;CdS∶Ce3+纳米带的光致发光谱的谱峰位于523和535nm处;CdS∶Er3+纳米带的光致发光谱中观察到3个强的发光峰,分别位于525、556和582nm处。     

Growth and photoluminescence of CdS and CdS:Mn Nanoribbons

CdS and CdS:Mn²⁺ Nanoribbons (NRs) are synthesized via a facile thermal evaporation approach. Their corresponding optical properties are investigated by room-temperature photoluminescence measurements. The spectrum of the undoped CdS NRs features four emission peaks: an intensive sharp one and three wide ones centered at 504 nm, 681 nm, 743 nm and 802 nm, respectively. The origins of them are discussed in detail. After doping with Mn²⁺ ions, only the host band-edge emission is retained, therefore, CdS:Mn²⁺ NRs present well narrow green band luminescence without any emission peaks from the Mn²⁺ ion. This property is quite meaningful for contributing in color light devices.     

Effect of heat-treatment on CdS and CdS/ZnS nanoparticles

Mono-dispersed and spherical cadmium sulfide (CdS) nanoparticles and cadmium sulfide/zinc sulfide (CdS/ZnS) nanoparticles, 4–5 nm in diameter, were synthesized in a heptane-AOT-water microemulsion system. The heat treatment of CdS and CdS/ZnS nanoparticles was annealed at 570 °C under the air atmosphere. The heat-treated nanoparticles were of variable large sizes and had enhanced crystallinity. UV–Vis spectra of heat-treated CdS and CdS/ZnS nanoparticles revealed a flat shape similar to that of bulk CdS compounds. The difference between the PL emission bands of organic-coated nanoparticles and heat-treated nanoparticles was small. The PL emission energy of heat-treated nanoparticles was improved by about 2–3 times compared with that of organic-coated nanoparticles.     

Investigation of structural and optical properties of the CdS and CdS/PPy nanowires

In this study, cadmium sulfide (CdS), polypyrrole (PPy) nanowires, and their heterojunctions have been electrochemically synthesized. Morphology of the nanowires has been investigated by scanning electron microscopy. Energy dispersed X-ray, X-ray diffraction, UV–Vis, and FTIR analyses have been used to confirm structure of both CdS and PPy nanowires. For the first time with this study, CdS/PPy nanowire heterojunctions have been integrated into photoelectrochemical (PEC) cells. It has been also demonstrated that PEC performance of the nanowires was strongly function of production conditions, such as deposition time and voltage. The maximum power conversion efficiency of the CdS nanowires obtained in this study was 1.36%. Moreover, efficiencies of the CdS/PPy nanowires have been reached to 5.00%, which makes them very favorable for PEC applications.     

CdS Nanoscale Photodetectors

CdS nanostructures have received much attention in recent years as building blocks for optoelectronic devices due to their unique physical and chemical properties. This progress report provides an overview of recent research about rational design of CdS nanoscale photodetectors. Three kinds of photodetectors according to the metal‐semiconductor contact types are discussed in detail: Ohmic contact, Schottky contact, and field enhanced transistor configuration. The focus is on the tuning of optical and electrical properties CdS nanostructures by element doping, composition and bandgap engineering, and heterojunction integration, along with thus modified device performances generated during these tuning processes. Latest concepts of photodetector design such as flexible, self‐powered, plasmonic, and piezophototronic photodetectors with novel properties are introduced to demonstrate the future directions of such an exciting research field.     

有机-无机复合CdS纳米晶的制备及表征

本文采用液液两相法,在甲苯、甲醇和水两相体系中制备了烷基硫醇和芳杂环硫醇修饰的有机-无机复合的CdS半导体纳米晶.通过紫外可见吸收光谱、X-射线光电子能谱、X-射线粉末衍射、透射电子显微镜、元素分析和热重分析检测手段对样品的结构和组成进行了表征.结果表明:该方法所制备的硫化镉纳米晶是由无机纳米核及通过化学键吸附在其表面的硫醇分子所组成.纳米晶的平均粒径约为5nm,尺寸均匀,稳定性高,在空气中可长时间保存.