量子点在生物化学分析中的应用

介绍了量子点的基本特性,对量子点在生物化学分析中的应用进行了综述,并展望了其发展趋势和应用前景。     

发光碳量子点的合成与毒性

综述了近几年国内外碳量子点的研究现状,对电弧法、激光剥蚀法、电化学法、燃烧-水热法、模板法等合成碳量子点的方法进行了介绍,论述了碳量子点的发光性质及毒性。碳量子点有望取代传统半导体量子点,在生物成像、发光探针分析等领域进行广泛的应用。     

全无机铯铅卤钙钛矿量子点的研究进展

全无机铯铅卤钙钛矿〔CsPbX3(X=Cl、Br、I)〕量子点稳定性高、色纯度好、量子产率高,受到人们广泛关注.然而,CsPbX3量子点中组分铅的毒性限制了CsPbX3量子点的进一步应用,同时,如何进一步提升其性能和稳定性也备受关注.首先,对CsPbX3量子点进行了简介;接着,对离子掺杂CsPbX3量子点、表面包覆CsPbX3量子点、表面钝化CsPbX3量子点的研究进展进行了综述;离子掺杂、不同材料表面包覆、表面钝化提高了CsPbX3钙钛矿量子点的稳定性.最后,对CsPbX3量子点未来的发展方向进行了展望.     

量子点标记DNA的应用与进展

量子点作为新型纳米微晶,在生物标记方面有着无与伦比的应用前景.综述了量子点标记DNA的方法,以及量子点-DNA探针在检测DNA、蛋白质及DNA之间相互作用等领域的最新应用和进展.并对DNA探针在未来的应用进行了展望.     

量子点的制备及其在药物检测和药物递送领域中的应用

近年来,随着纳米材料的日新月异,量子点因其独特的光学性质,受到广大科技工作者的研究。随着人们对生命健康意识的不断提高,药物检测和药物传递系统的研究也已成为研究的热潮。本文对量子点的特性、制备方法、表面修饰技术及量子点在药物检测和药物递送系统中的应用进行综述,并对量子点在药物实时监测和药物靶向治疗方面进行展望。     

量子点的制备及其在生物医学中的应用进展

量子点作为一种优良的荧光半导体纳米粒子,已成为纳米技术领域最受关注的研究对象之一,并成功应用于生命科学等领域。随着小粒径的低毒无镉量子点的制备和量子点荧光共振能量转移等新技术的发展,量子点在生命科学领域将展示出更大的应用空间。本文介绍了量子点的基本概念和性质,探讨了近年来在有机溶剂和水溶液两种不同介质中制备量子点的方法,并分析比较了其优缺点;对量子点在生物医学领域(包括蛋白质和核酸研究、组分检测、荧光编码及细胞标记等)的应用进行了综述和展望,指出了目前存在的问题和今后的发展方向。     

核壳量子点研究进展

核壳量子点是半导体材料研究热点之一。介绍了核壳量子点各种结构及其应用,着重综述了近年来有机合成路线制备核壳量子点方法,包括高温入注法、交替离子层吸附生长法、单前体法、种子生长法、离子交换法、一锅法等,并简述了各自的实验原理。最后对核壳量子点的制备研究进行了展望。     

量子点分子信标的制备及其在核酸检测中的应用

量子点具有耐光漂白、颜色可调、一元激发/多元发射以及发射光谱窄等特性,故将其应用在分子信标中,必将克服传统有机染料的很多缺点。量子点分子信标不但灵敏度高、光稳定性好,而且可以进行多重检测。本文就近几年来量子点分子信标的发展进行了综述,其中针对量子点的制备系统阐述了可用于制备分子信标的量子点类型、量子点与分子信标连接的方式、量子点分子信标猝灭剂的选择及其表征。同时还详细介绍了量子点分子信标在多重SNP测定、细胞内病毒表达等核酸检测中的应用。     

全无机铯铅卤钙钛矿量子点的研究进展

全无机铯铅卤钙钛矿（CsPbX3（X=Cl、Br、I））量子点稳定性高、色纯度好、量子产率高,受到人们广泛的关注。然而,CsPbX3量子点中组分铅的毒性限制了CsPbX3量子点的进一步应用,同时,如何进一步提升其性能和稳定性也备受关注。文章首先对CsPbX3量子点进行了简介,进而综述了选择合适的方法包括掺杂控制其晶粒尺寸、包覆钝化提高稳定性等（包覆剂、钝化剂、技术方法等）的研究进展。最后,笔者对CsPbX3量子点未来的发展方向进行了展望。     

量子点敏化太阳能电池研究进展

综述了量子点敏化太阳能电池的结构、工作原理和量子点敏化剂的沉积方式、对电极的制备及性能、量子点敏化剂的改性以及半导体薄膜的制备方法,最后结合现存问题提出了今后的研究方向。     

多层核壳CuInS_2/ZnS量子点的有机相合成的研究

有机相反应体系中合成制备CuInS2量子点核壳结构,并对制备出的核以及核壳结构的材料进行表征。XRD结果显示成功合成纯度高、晶形较好的CIS量子点;通过TEM可以观察到量子点形貌以及尺寸的变化;荧光光谱和吸收光谱则清楚表明在反应过程中红移和蓝移情况以及量子效率的明显增加;最后,由光稳定性实验得出包覆了ZnS的CIS量子点稳定性得到提高。     

Growth of InAs Quantum Dots on Germanium Substrate Using Metal Organic Chemical Vapor Deposition Technique

Self-assembled InAs quantum dots (QDs) were grown on germanium substrates by metal organic chemical vapor deposition technique. Effects of growth temperature and InAs coverage on the size, density, and height of quantum dots were investigated. Growth temperature was varied from 400 to 450 °C and InAs coverage was varied between 1.40 and 2.35 monolayers (MLs). The surface morphology and structural characteristics of the quantum dots analyzed by atomic force microscope revealed that the density of the InAs quantum dots first increased and then decreased with the amount of InAs coverage; whereas density decreased with increase in growth temperature. It was observed that the size and height of InAs quantum dots increased with increase in both temperature and InAs coverage. The density of QDs was effectively controlled by growth temperature and InAs coverage on GaAs buffer layer.     

用于生物标记的半导体量子点研究

半导体量子点的独特光学性质使之成为理想的荧光探针材料，在生物医学领域具有广阔的应用前景．本文评述了目前量子点合成、表面修饰、结合生物分子的方法，以及半导体量子点在生物标记应用中相对于传统有机染料的优点．     

Toward quantitatively fluorescent carbon-based "quantum" dots

Carbon-based "quantum" dots (or "carbon dots") are generally defined as surface-passivated small carbon nanoparticles that are brightly fluorescent. Apparently, the carbon particle surface passivation in carbon dots is critical to their fluorescence performance. An effective way to improve the surface passivation is to dope the surface of the precursor carbon nanoparticles with an inorganic salt, followed by the typical functionalization with organic molecules. In this work we passivated small carbon nanoparticles by a combination of the surface-doping with nanoscale semiconductors and the organic functionalization, coupled with gel column fractionation to harvest the most fluorescent carbon dots, which exhibited fluorescence emission quantum yields of up to 78%. Experimental and mechanistic issues relevant to potentially further improve the performance of carbon dots toward their being quantitatively fluorescent are discussed.     

Surface passivation of CdSe-TOPO quantum dots by poly(acrylic acid): solvent sensitivity and photo-induced emission in water

The principal available methods for the preparation of high quality CdSe quantum dots (QDs) are based on organic ligands such as tri-n-octylphosphine oxide (TOPO) which lead to non-water soluble nanocrystal QDs. As most biological interactions take place in aqueous media, much effort has been made on preparation of water soluble QDs. In this report, the water soluble CdSe QDs were prepared via a ligand exchange process between organic soluble CdSe-TOPO quantum dots and poly(acrylic acid). The poly(acrylic acid) (PAA) can attach onto the surface of CdSe-TOPO quantum dots in a ligand exchange process to make water-soluble CdSe-PAA complexes. In spite of CdSe-TOPO QDs, the resultant CdSe-PAA QDs are soluble in polar solvents such as methanol or water. Optical properties of CdSe-PAA QDs in several solvents showed that the emission intensity of QDs was mainly decreased in protic solvents such as methanol or water. The TEM images of dots in different solvents were examined and some aggregation of dots was found in protic solvents. In comparison with PAA, the addition of PDMAEMA to the solution of CdSe-TOPO QDs in THF increased the emission intensity of QDs. Furthermore, we found that the entitled ligand exchange process was fast and conjugation process completed at short time intervals. The UV-irradiation of the CdSe-PAA conjugate in water showed that the emission was amplified by increasing the irradiation time.     

提高钙钛矿量子点稳定性的研究进展

钙钛矿量子点具有发光谱带较窄、发光可调、量子效率高等优异的光学性能,在发光二极管、激光发射器等领域广受关注。但是钙钛矿量子点由于强离子性、高表面能及表面配体易迁移等特性而对环境高度敏感,使其在实际应用中受到限制。本文简要介绍了钙钛矿量子点结构和不稳定的原因,综述了近年来提高钙钛矿量子点稳定性的主要方法,重点从离子掺杂、表面钝化、表面包覆及多重保护4个方面展开论述。最后从绿色环保的角度出发,对高稳定生物质基钙钛矿量子点材料的制备进行了展望,提出使用具有特定结构的生物质材料及其衍生材料取代传统石油基试剂作为配体、溶剂或吸附重金属离子的外壳材料,可加速钙钛矿量子点朝着绿色低毒的方向发展。     

金属卤化物钙钛矿量子点的制备及其光催化应用研究进展

利用太阳能光催化技术生产清洁燃料、降解污染物及转化高附加值产品，是解决当前能源短缺和环境污染问题的有效途径。随着对金属卤化物钙钛矿的深入研究，成功开发出一系列能够制备出成分和形貌控制精确、产物均匀性好、结晶度高的钙钛矿量子点的合成方法，使钙钛矿量子点应用到光催化领域中。综述了热注入法、配体辅助再沉淀法、溶剂热法、微波辅助法等金属卤化物钙钛矿量子点的合成方法及金属卤化物钙钛矿量子点在光催化析氢、光催化还原二氧化碳、光催化合成有机物以及光催化降解有机物等方面的研究进展，最后对金属卤化物钙钛矿光催化剂的发展前景进行了展望。     

Photoluminescence Intermittency from Single Quantum Dots to Organic Molecules: Emerging Themes

Recent experimental and theoretical studies of photoluminescence intermittency (PI) or “blinking” exhibited by single core/shell quantum dots and single organic luminophores are reviewed. For quantum dots, a discussion of early models describing the origin of PI in these materials and recent challenges to these models are presented. For organic luminophores the role of electron transfer, proton transfer and other photophysical processes in PI are discussed. Finally, new experimental and data analysis methods are outlined that promise to be instrumental in future discoveries regarding the origin(s) of PI exhibited by single emitters.     

Facile solution growth of vertically aligned ZnO nanorods sensitized with aqueous CdS and CdSe quantum dots for photovoltaic applications

Vertically aligned single crystalline ZnO nanorod arrays, approximately 3 μm in length and 50-450 nm in diameter are grown by a simple solution approach on a Zn foil substrate. CdS and CdSe colloidal quantum dots are assembled onto ZnO nanorods array using water-soluble nanocrystals capped as-synthesized with a short-chain bifuncional linker thioglycolic acid. The solar cells co-sensitized with both CdS and CdSe quantum dots demonstrate superior efficiency compared with the cells using only one type of quantum dots. A thin Al2O3 layer deposited prior to quantum dot anchoring successfully acts as a barrier inhibiting electron recombination at the Zn/ZnO/electrolyte interface, resulting in power conversion efficiency of approximately 1% with an improved fill factor of 0.55. The in situ growth of ZnO nanorod arrays in a solution containing CdSe quantum dots provides better contact between two materials resulting in enhanced open circuit voltage.     

Superlattices: problems and new opportunities,nanosolids

Superlattices were introduced 40 years ago as man-made solids to enrich the class of materials for electronic and optoelectronic applications. The field metamorphosed to quantum wells and quantum dots, with ever decreasing dimensions dictated by the technological advancements in nanometer regime. In recent years, the field has gone beyond semiconductors to metals and organic solids. Superlattice is simply a way of forming a uniform continuum for whatever purpose at hand. There are problems with doping, defect-induced random switching, and I/O involving quantum dots. However, new opportunities in component-based nanostructures may lead the field of endeavor to new heights. The all important translational symmetry of solids is relaxed and local symmetry is needed in nanosolids.