基于准一维CdS纳米结构的合成及应用

针对准一维硫化镉（CdS）纳米结构的合成及其器件作了相应介绍。硫化镉（CdS）作为一种II-VI族半导体材料,室温禁带宽度为2.42 eV,合成方法多种多样,可根据具体的需求和条件,通过对各种具体参数的调节,合成出需要的CdS纳米结构及高质量的准一维CdS纳米结构制备出高性能器件。虽然准一维CdS纳米结构的合成和器件制...     

ZnSe纳米材料及界面的制备与表征

利用热蒸发法对ZnSe纳米材料的相控合成进行了研究,制备了多种具有稳定闪锌矿和亚稳纤锌矿结构的ZnSe纳米材料,如ZnSe纳米线、纳米圈、纳米轮及三晶纳米带。同时,在相控合成基础上,通过改变管式炉内反应压强获得了几种同质与异质界面。利用多种透射电子显微学手段对合成的ZnSe纳米材料及相关同质与异质界面进行了深入表征,并对ZnSe纳米材料的生长机理进行了探讨。     

钛酸铅超细纳米晶及纳米线的制备与结构表征

近来，一维纳米材料吸引了物理学、材料学和化学界的广泛关注，成为纳米材料研究的热点。纳米线是物质在纳米尺度上的一种特殊结构，其优异的光学、电学和力学性能，在纳米器件的应用领域极具发展前景。纳米线的制备技术及物性的测量是材料在纳米原型器件制作和应用的关键，不断探索低维纳米材料的制备新技术，合成出多种材料的纳米线具有重要意义。     

名词释义——准一维纳米材料

准一维纳米材料是指在两维方向上为纳米尺度，长度为宏观尺度的新型纳米材料。如纳米棒、纳米线、半导体纳米量子线、纳米线阵列等都属于准一维纳米材料。这些新型材料的实验研究，为进一步研究纳米结构和准一维纳米材料的性能，建立准一维纳米材料的新理论和推进它们在纳米结构器件中的应用奠定了基础。     

一维ZnSe半导体纳米材料的制备与特性

在三种新溶剂三乙胺、二乙胺、三乙醇胺中,以KBH4为还原剂,由改进的溶剂热方法于170℃制备了ZnSe纳米材料,XRD、TEM研究表明最终产物为一维ZnSe半导体纳米晶材料,室温产物为球形ZnSe纳米材料.初步研究了一维ZnSe纳米材料的光学吸收和热稳定性.结果表明,不同条件(溶剂,温度)下ZnSe具有不同的形貌;ZnSe在常温下具有一定稳定性,400℃以上时在空气中可转化为ZnO纳米材料;并用过渡态配合物的概念解释了实验现象.     

一维纳米材料位姿调控与激光连接技术进展

一维纳米材料在微/纳机电系统、柔性透明导电器件、传感器等领域具有广泛的应用。将一维纳米材料装配至指定位置并以特定姿态与纳观或宏观材料形成连接是纳米结构实现功能化、器件化的关键。当前已有多种对一维纳米材料进行位姿调控的方法,根据这些调控方法的原理,将其分为探针法、自组装和光镊法三类,重点介绍了这三种一维纳米材料位姿调控方法的原理与特点。结合一维纳米材料的位姿调控方法与激光连接过程,详细阐述了激光连接一维纳米材料领域的新进展。     

准一维半导体纳米材料的研究进展

探索准一维纳米结构材料的维数和尺寸,对其光学、电学和力学等性质的影响有很大的研究价值。介绍了半导体纳米棒、纳米线、纳米带等典型准一维纳米材料的一些最新研究进展,并对准一维纳米材料的研究趋势作了展望。     

激光烧蚀法制备准一维纳米材料

介绍了当前激光烧蚀法制备纳米丝、纳米管和纳米电缆的研究现状,讨论了准一维纳米材料激光烧蚀法制备的系统设备和制备条件,分析了激光烧蚀法制备准一维纳米材料的特点和发展趋势.认为准一维纳米材料是气相粒子在高温催化剂作用下生成的.激光烧蚀法具有洁净、可控性强及适应面广的特点.     

纳米线、纳米管的制备、表征及其应用

在高度集成化浪潮的推动下,现代技术对纳米尺度功能器件的需求将越来越迫切。纳米线、纳米管等一维材料作为纳米器件中必不可少的功能组件,在纳米研究领域中的地位显得愈发重要。本文从一维纳米材料的研究范畴入手,介绍了纳米线、纳米管的制备方法,技术要点以及各种相关表征方法,并涉及了当前一维纳米材料的一些应用研究,为基于纳米线、纳米管功能器件的研制提供前期参考。     

准一维纳米结构的电子显微学研究

自从１９９１年，Ｉｉｊｉｍａ发现纳米碳管［１］以来，一系列准一维纳米材料被相继用不同方法合成出来。由于其独特的结构特性和因此而具有的不同于体材料的新颖的物理性质，这些准一维纳米材料有着很大的基础研究价值和潜在的应用价值，因而受到人们的广泛研究和关注。...     

Synthesis and photoluminescence properties of wash-board belt-like ZnSe nanostructures

Washboard belt-like zinc selenide （ZnSe） nanostructures are successfully prepared by a simple chemical vapor deposi- tion （CVD） technology without catalyst. The phase compositions, morphologies and optical properties of the nanos- tructures are investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, high-resolution transmis- sion electron microscopy （HRTEM） and photoluminescence （PL） spectroscop, respectively. A vapor-liquid mecha- nism is proposed for the formation of ZnSe belt-like structures. Strong PL from the ZnSe nanostructure can be tuned from 462 nm to 440 nm with temperature varying from 1000 ℃ to 1200 ℃, and it is demonstrated that the washboard belt-like ZnSe nanostructures have potential applications in optical and sensory nanotechnology. This method is ex- pected to be applied to the synthesis of other II-VI groups or other group＇s semiconducting materials.     

One-dimensional nanostructures for electronic and optoelectronic devices

One-dimensional (1-D) nanostructures have been the focus of current researches due to their unique physical properties and potential applications in nanoscale electronics and optoelectronics. They address and overcome the physical and economic limits of current microelectronic industry and will lead to reduced power consumption and largely increased device speed in next generation electronics and optoelectronics. This paper reviews the recent development on the device applications of 1-D nanostructures in electronics and optoelectronics.First, typical 1-D nanostructure forms, including nanorods,nanowires, nanotubes, nanobelts, and hetero-nanowires,synthesized from different methods are briefly discussed.Then, some nanoscale electronic and optoelectronicdevices built on 1-D nanostructures are presented,including field-effect transistors (FETs), p-n diodes,ultraviolet (UV) detectors, light-emitting diodes (LEDs),nanolasers, integrated nanodevices, single nanowire solar cells, chemical sensors, biosensors, and nanogenerators.We then finalize the paper with some perspectives and outlook towards the fast-growing topics.     

Synthesis,field emission and optical properties of ZnSe nanobelts,nanorods and nanocones by hydrothermal method

ZnSe nanostructures, such as nanobelts, nanorods and nanocones, were successfully synthesized on Zn foils via a hydrothermal method using EDTA as soft template at low temperature. EDTA played a significant role on the morphology of ZnSe nanomaterials. X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and energy dispersive spectrometer (EDS) were carried out to characterize the microstructures and chemical compositions of the as-synthesized ZnSe samples. XRD patterns indicated that the as-synthesized ZnSe samples belonged to a cubic zinc blende structure. SEM observation obviously showed that the nanocones had very sharp tips compared to nanorods and nanobelts. The field emission (FE) measurement showed that the as-synthesized ZnSe nanocones had a lower turn-on field of ~1.6 V μm⁻¹ at the current density of 10 μA cm⁻². A high field enhancement factor of ~4514 was achieved for the ZnSe nanocones. The superior field emission properties were probably attributed to the sharp tips of the ZnSe nanocones. Room temperature photoluminescence (PL) spectroscopy of the ZnSe nanostructures showed a wide band emission from blue light to orange light. The as-prepared ZnSe nanomaterials have promising applications in optoelectronic devices. A possible formation mechanism of ZnSe nanobelts, nanorods and nanocones was also proposed and discussed.     

Tunable Hierarchical Metallic‐Glass Nanostructures

Synthesizing metallic nanostructures with control over morphology, surface chemistry, and length‐scale is important for a wide range of applications. Nanostructures having large surface area paired with suitable chemistry are particularly desirable in catalytic applications to facilitate the reaction kinetics. However, the techniques used for nanostructure synthesis are often lengthy, difficult, require expensive precursors/stabilizers, and limit the control over nanostructure morphology/chemistry. Here tuning metallic‐glass nanostructures to a wide range of morphologies, where the surface is enriched with catalytic noble metal, is reported. By combining thermoplastic nanofabrication together with electrochemical processing, hierarchical metallic nanostructures with large electrochemical surface area and high catalytic activity are synthesized. Due to the versatility in processing and independent control over multiple length‐scales, the approach may serve as a tool‐box for fabricating complex hierarchical nanostructures for wide ranging applications.     

A Precursor‐Based Route to ZnSe Nanowire Bundles

A large number of one‐dimensional bundles of ZnSe nanowires with diameters ranging from 15–20 nm and lengths of up to tens of micrometers have been prepared via the thermal treatment of a ribbon‐like precursor (ZnSe·3ethylenediamine), which has been synthesized by a mixed solvothermal route, in an argon atmosphere. The as‐obtained precursor has been characterized by powder X‐ray diffraction (XRD), transmission electron microscopy (TEM), IR spectroscopy, thermogravimetric analysis, and elemental analysis. XRD and high‐resolution TEM characterization reveal that the as‐synthesized ZnSe nanowires have the single‐crystal hexagonal wurtzite structure with the [001] growth direction. The surface chemical composition of ZnSe nanowires has been studied by X‐ray photoelectron spectroscopy. The cooperative action of the mixed solvents may be responsible for the formation of the morphology of the resulting products. Room‐temperature photoluminescence measurements indicate the as‐grown ZnSe nanostructures have a strong emission peak centered at 587 nm and two weak emission peaks centered at 435 and 462 nm. The strong emission from the ZnSe nanostructures reveals their potential as building blocks for optoelectronic devices.     

Novel Nanostructures of Functional Oxides Synthesized by Thermal Evaporation

Functional oxides are the fundamentals of smart devices. This article reviews novel nanostructures of functional oxides, including nanobelts, nanowires, nanosheets, and nanodiskettes, that have been synthesized in the authors’ laboratory. Among the group of ZnO, SnO₂, In₂O₃, Ga₂O₃, CdO, and PbO₂, which belong to different crystallographic systems and structures, a generic nanobelt structure has been synthesized. The nanobelts are single crystalline and dislocation‐free, and their surfaces are atomically flat. The oxides are semiconductors, and have been used for fabrication of nanodevices such as field‐effect transistors and gas sensors. Taking SnO₂ and SnO as examples, other types of novel nanostructures are illustrated. Their growth, phase transformation, and stability are discussed. The nanobelts and related nanostructures are a unique group that is likely to have important applications in electronic, optical, sensor, and optoelectronic nanodevices.     

Wafer‐Scale Single‐Crystalline Ferroelectric Perovskite Nanorod Arrays

1D ferroelectric nanostructures are promising for enhanced ferroelectric and piezoelectric performance on the nanoscale, however, their synthesis at the wafer scale using industrially compatible processes is challenging. In order to advance the nanostructure‐based electronics, it is imperative to develop a silicon‐compatible growth technique yielding high volumetric density and an ordered arrangement. Here, a major breakthrough is provided in addressing this need and ordered and close‐packed single crystalline ferroelectric nanorod arrays, of composition PbZr_0.52Ti_0.48O₃ (PZT), grown on commercial grade 3 in. silicon wafer are demonstrated. PZT nanorods exhibit enhanced piezoelectric and ferroelectric performance compared to thin films of similar dimensions. Sandwich structured architecture utilizing 1D PZT nanorod arrays and 2D reduced graphene oxide thin film electrodes is fabricated to provide electrical connection. Combined, these results offer a clear pathway toward integration of ferroelectric nanodevices with commercial silicon electronics.     

X-ray photoelectron spectroscopy studies of ZnS<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Se<Subscript>1–<Emphasis Type="Italic">x</Emphasis></Subscript> nanostructures produced in a porous aluminum-oxide matrix

Semiconductor nanostructures on the basis of ZnS _x Se_1–x (x = 0, 0.1, 0.3, 0.5, 0.7, and 1.0) compounds are synthesized by the template method based on the formation of semiconductor nanoparticles in porous anodic aluminum-oxide templates upon the vacuum thermal evaporation of a mixture of ZnS and ZnSe powders. The results of studies of the elemental composition of the nanostructures in relation to the composition of the initial mixture and to the parameters of the matrix substrate by means of X-ray photoelectron spectroscopy are reported. It is shown that the composition of the nanostructures is close to the composition of the initial powders and can be specified by the ZnS/ZnSe ratio in the initial mixture.     

超高温金属纳米结构增强吸收特性的仿真研究

利用表面等离子体改变材料吸收光谱特性越来越受到关注。为了增强超高温金属纳米结构的吸收特性,设计了超高温金属-金属以及膜层-金属-金属表面等离子体周期纳米结构,仿真分析其在波长200~4 000 nm光谱范围内,不同参数对材料吸收谱特性的影响。仿真分析表明,不同参数的吸收光谱中均会出现吸收峰,且吸收率达93%以上。而介电材料、金属纳米结构的周期、尺寸和深度是影响吸收率的主要因素。同时,介电材料和周期还会对吸收峰出现的位置产生影响。该仿真结果为超高温表面等离子体材料的吸收特性应用的研究提供了理论基础。