重油残渣基新型碳功能材料的研究进展

综述了以重油残渣为原料,采用化学气相沉积法、共炭化法和微波等离子体法可控制备气相生长碳纤维、碳微球、内包铁洋葱状富勒烯、纳米碳管、内包金属碳微米颗粒及定向碳纳米薄膜等各种高附加值碳材料;采用等离子体氧化法、酸处理法、化学还原法等方法对气相生长碳纤维和碳微球进行表面修饰,在产物表面引入含氧官能团,解决了可溶性碳材料的制备问题;在碳微球表面引入Pt纳米颗粒,使重油残渣基新型碳材料在表面修饰和功能化后可望成为性能优异的吸附和催化材料.     

直流碳弧法制备碳包覆铁纳米颗粒机理研究

采用直流碳弧等离子体法成功制备了碳包覆铁纳米颗粒,利用透射电子显微镜和高分辨透射电子显微镜、X射线衍射、X射线能谱仪对样品的形貌、物相结构、化学成分和粒度进行表征分析,并对碳包覆纳米金属颗粒的形成机理进行初步探讨。结果表明:直流碳弧等离子体技术制备的碳包覆纳米金属颗粒具有明显的铁核(bcc-Fe)/碳壳(石墨层片)包覆结构,颗粒大多呈球形和椭球形,粒径分布在20~60nm范围,平均粒径为44nm,铁粒子外碳层的厚度为5~8nm。碳包覆铁纳米铁颗粒是通过颗粒内部固态形式的碳自行扩散至颗粒表面和颗粒外部气态形式的碳沉积到颗粒表面形成的。     

聚乙烯基吡咯烷酮/丙烯酸水凝胶吸附金银纳米颗粒的研究

将辉光放电电解等离子体引发合成的聚乙烯基吡咯烷酮/丙烯酸(PVP/AAc)水凝胶用于吸附化学还原和晶种诱导结合法制备银球、金棒和Au_(rod)@Ag核壳纳米颗粒。采用红外光谱和扫描电镜对凝胶的结构和形貌进行表征,采用紫外-可见分光光度计和透射电子显微镜对核壳纳米颗粒进行表征。结果表明:该凝胶对水相中的金银纳米粒子有很强的吸附能力,尤其对近球形纳米粒子更具有良好的吸附效果。PVP/AAc水凝胶可用于水相中纳米粒子的富集、分离及回收。     

液相等离子沉积非晶态碳膜的试验研究

应用简单的电镀槽，通过阴极/电解液界面前沿气泡鞘的形成而建立辉光放电，促成非晶态碳薄膜在电极表面的沉积。沉积物宏观上分布不均匀，在阴极浸入电解液的末端，由于电流的尖端效应，导致生成物为石墨。而远离末端为正常沉积区，表面平整光滑，生成物为非。晶态碳膜。结论：液相等离子沉积行为可发生在辉光放电条件下的阴极过程，从而可应用于非晶态薄膜如非晶态碳的制备。     

修饰纳米CdS/聚合物的界面相互作用与光学性能

采用微乳液法结合原位表面修饰合成了纳米尺度的硫化镉粒子,采用溶液共混和静态铺膜方法制备了纳米粒子/聚合物复合体系,以研究纳米粒子与聚合物间的界面作用.结果表明,经修饰的纳米CdS粒子比较均匀地分散于聚合物基体内,纳米粒子与聚合物基体间存在较强的相互作用.根据复合体系的紫外-可见吸收光谱和荧光光谱,分析了表面修饰(表面修饰剂种类、表面修饰剂用量等)对纳米粒子的分散以及复合体系界面特性的影响,证实了表面修饰剂具有促进纳米粒子分散和消除粒子表面缺陷的作用.     

聚乙烯吡咯烷酮表面修饰氧化锌纳米粒子的合成与表征

以N,N-二甲基甲酰胺为溶剂,乙酸锌为前驱物,聚乙烯吡咯烷酮为表面修饰剂,采用溶液化学法,制备了氧化锌纳米粒子。通过紫外-可见吸收光谱(UV-Vis)、荧光光谱(FL)和透射电子显微镜(TEM)等方法对合成的氧化锌纳米粒子进行表征。结果表明:所合成样品具有量子尺寸效应,样品UV-Vis吸收光谱在335~350 nm给出了氧化锌纳米粒子的特征吸收峰;FL光谱显示在400,550 nm处产生荧光发射;氧化锌纳米粒子的尺寸在100 nm左右且粒径分布较窄,表明聚乙烯吡咯烷酮对氧化锌纳米粒子的表面起到良好的修饰作用。     

自组装Ag纳米颗粒的表面等离子体共振及其对CdSe量子点的荧光增强效应

采用柠檬酸三钠还原硝酸银的方法制备了Ag纳米粒子溶胶,利用静电自组装技术制得单分散Ag纳米颗粒薄膜.研究了该Ag纳米颗粒薄膜的光学特性,通过改变反应物浓度和后期的热退火温度,有效调控了Ag纳米颗粒尺度和其在外场作用下产生的表面等离子体共振(SPR)特性.将所制备的Ag纳米颗粒薄膜与CdSe量子点耦合,利用SPR对荧光的...     

Fe3O4/CdTe磁性荧光纳米复合物的逐步杂凝聚法合成及其表征

采用逐步杂凝聚法合成了Fe3O4/CdTe磁性荧光纳米复合物.以化学共沉淀法制备Fe3O4纳米颗粒,经油酸修饰后分散在表面活性剂中形成磁流体.CdTe量子点以巯基乙酸为稳定剂制得.最后以聚乙烯亚胺(PEI)为联接剂,成功制备了Fe3 O4 /CdTe磁性荧光双功能纳米复合物颗粒.该复合物颗粒平均尺寸为(30±5)nm,荧光产率为0.186,饱和磁化强度为15.745emu/g,该纳米粒子既具有优异的荧光特性,也具有较强的超顺磁性.     

以混合双表面活性剂作修饰剂制备磁性液体

在Fe(CO)5热分解法制备煤油基金属铁磁性液体中,采用两种表面活性剂OA(油酸)与T154A(聚异丁烯丁二酰亚胺)以质量比1∶1混合后共同修饰纳米铁磁性颗粒,制备分散性好、磁饱和强度高的磁性液体。制备的样品由XRD、TEM、VSM和FTIR进行表征。从表征结果知,制备出的磁性纳米颗粒主要为金属铁;磁性纳米颗粒呈现较为规则的球形颗粒,分散性好,平均粒径约为10nm;磁性液体的磁饱和强度Ms约为63emu/g,矫顽力和剩磁几乎为零;与OA单独修饰制备的磁性液体相比,磁性纳米颗粒表面同时被OA+T154A修饰的磁性液体在抗氧化性、分散性和磁饱和强度方面皆有所提高。     

磁性/荧光双功能纳米颗粒的制备及性能研究

通过对Fe3O4纳米颗粒的SiO2包覆和表面胺基化修饰,成功地将CdSe量子点（QDs）均匀地包覆在Fe3O4纳米粒子表面,制备了稳定的、具有磁性/荧光双功能的纳米颗粒,结果表明,所制备的纳米颗粒具有良好的分散性、优异的磁响应特性和荧光发射性能,为制备该类双功能纳米材料,拓宽其应用领域提供了新的途径。     

真空度对碳纳米管生长过程的影响

利用等离子体增强热丝化学气相沉积系统在沉积有过渡层Ta和催化剂层NiFe的Si衬底上制备出准直碳纳米管，并用扫描电子显微镜研究了它们的生长和结构，结果表明真空度对其生长和结构有较大的影响。当真空度为4000Pa和2000Pa时，准直碳纳米管较容易生长，并且真空度为2000Pa时生长的碳纳米管平均长度大于真空度为4000Pa时碳纳米管的平均长度。但真空度为667Pa时碳纳米管生长困难。根据热力学和辉光放电理论，分析了真空度对准直碳纳米管生长和结构的影响。     

辉光放电和压强对准直碳纳米管生长的影响

利用负偏压增强热丝化学气相沉积系统在沉积有过渡层Ta和催化剂层NiFe的Si村底上制备出准直碳纳米管，并用扫描电子显微镜研完了它们的生长和结构，结果表明辉光放电和压强对其生长和结构有极大的影响。若无辉光放电产生，碳纳米管是弯曲的，有辉光放电时，碳纳米管是准直的。当压强较大时，准直碳纳米管较容易生长，并且随着压强的减小，其平均直径减小和平均长度增大。但压强为5Pa时，准直碳纳米管却不能够生长。最后，分析和讨论了辉光放电和压强对准直碳纳米管生长和结构的影响。     

Ag nanoparticle incorporation in mesoporous silica synthesized by solution plasma and their catalysis for oleic acid hydrogenation

The incorporation of Ag nanoparticles on mesoporous silica as the supporting material and their catalysis for oleic acid hydrogenation were described in this study. The template removal and Ag nanoparticle incorporation were concurrently taken place in the novel glow discharge in a solution, namely solution plasma process under controlled conditions. With only 15 min of discharge time, Ag nanoparticles were incorporated on the mesoporous silica matrix confirmed by the evidences of XRD and TEM and the template inside mesopores was mostly removed confirmed by FTIR spectra. The hydrogenation catalysis of oleic acid was preliminarily tested using UV-VIS spectroscopy after oxidation using permanganate ions (MnO₄⁻). It was found that the conversion was observed to be 12.83% in the butanol system and reached to 90.56% in ethanol.     

碳包覆碳化钛壳／核型纳米材料制备及其电催化性能

采用直流电弧等离子体法,在甲烷和氢气混合气氛下蒸发块体钛,制备出碳包覆碳化钛（C@TiC）壳／核型纳米结构粒子,利用x射线衍射仪、拉曼光谱仪和透射电子显微镜进行了物相、结构及形貌表征,结果表明,所制备的纳米粒子为碳包覆碳化钛结构,其碳包覆层厚度约1nm,部分纳米粒子呈现规则的六棱形貌。利用涂层法将碳包覆碳化钛纳米粉体制成电极,并通过循环伏安测试及电化学降解2,4－二氯酚实验,研究了碳包覆碳化钛纳米粒子的电化学性能及有机物降解性能。在一定负压范围内,碳包覆碳化钛纳米材料电极的降解效率随着负向电压的增大而增大;当电压为－1．0v时,其降解速率为8．55mg／（L·h）;当电压为-0．5v时,降解速率为7．57mg／（L·h）。     

Carbon Nanotubes Grown on the Surface of Cathode Deposit by Arc Discharge

Carbon nanotubes prepared by de arc discharge of graphite electrodes in He and CH₄ gas took markedly different morphology. Thick nanotubes embellished with many carbon nanoparticles were obtained by evaporation under high CH₄ gas pressure and high arc current. Thin and long carbon nanotubes were obtained under a CH₄ gas pressure of 50Torr and an arc current of 20A for the anode with a diameter of 6mm.     

Carbon nanotube synthesis over glow discharge-treated Ni/AAO membrane

Glow discharge plasma has been widely used in metal supported catalyst preparation. In this paper, this non-thermal plasma was applied for the fabrication of Ni/AAO membrane. This process, including incipient wetness impregnation, drying, plasma treatment and calcinations, is similar with the preparation of supported catalyst. XPS analysis of Ni/AAO membrane indicated the enrichment of nickel element in membrane nanopores during plasma treatment. As-prepared AAO membrane was used in the synthesis of carbon nanotube arrays by corona discharge enhanced chemical vapor deposition. They were much different in morphology with that from conventional Ni/AAO membrane without glow discharge treatment. In addition, the NiO nanoparticles were highly dispersed in nanotube walls.     

A synthesis of fluorescent starch based on carbon nanoparticles for fingerprints detection

A pyrolysis method for synthesizing carbon nanoparticles (CNPs) were developed by using malic acid and ammonium oxalate as raw materials. The incorporation of a minor amount of carbon nanoparticles into starch powder imparts remarkable color-tunability. Based on this phenomenon, an environment friendly fluorescent starch powder for detecting latent fingerprints in non-porous surfaces was prepared. The fingerprints on different non-porous surfaces developed with this powder showed very good fluorescent images under ultraviolet excitation. The method using fluorescent starch powder as fluorescent marks is simple, rapid and green. Experimental results illustrated the effectiveness of proposed methods, enabling its practical applications in forensic sciences.     

Carbon Nanotubes Grown on the Surface of Cathode Deposit by Arc Discharge

Abstract

Carbon nanotubes prepared by de arc discharge of graphite electrodes in He and CH₄ gas took markedly different morphology. Thick nanotubes embellished with many carbon nanoparticles were obtained by evaporation under high CH₄ gas pressure and high arc current. Thin and long carbon nanotubes were obtained under a CH₄ gas pressure of 50Torr and an arc current of 20A for the anode with a diameter of 6mm.     

New method for synthesis of Pt nanoparticles embedded in a carbon matrix

Platinum (Pt) nanoparticles embedded in a carbon matrix were synthesized for the first time in benzene by an electric plasma discharge generated in the cavitation field of benzene due to an ultrasonic horn. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to study the particle size, structure and morphology of the synthesized nanoparticles. The Pt nanoparticles have FCC bulk Pt crystal structure. On the average Pt nanoparticle diameter ranged from 8 nm to 40 nm when synthesized at 4.1 kV and from 5 nm to 25 nm when synthesized at 3.4 kV. X-ray photoelectron Spectroscopy (XPS) and Energy dispersive X-ray Spectroscopy (EDX) were used to study the chemical composition of the synthesized nanoparticles. A cost effective new method for carbon supported Pt nanoparticles will be of potential interest in fuel cell and catalysis applications.     

Liquid-Phase Preparation and Characterization of Zinc Oxide Nanoparticles

Zinc oxide (ZnO) nanoparticles have been prepared by a wet chemical method, from zinc acetate and LiOH ethanol-based solutions. The resulted nanoparticles were dispersed in a solvent. The effect of solvent (ethanol or butanol) and surfactant (polyethylene glycol-PEG 200) on the average size and size distribution of the nanoparticles was investigated by light scattering measurements. Smaller size was observed for ZnO nanoparticles dispersed in butanol and PEG 200. The statistical parameters of the Gaussian size distribution curves were calculated. ZnO nanoparticles have been prepared to be used as seeds on a substrate for the growth of ZnO nanowires. The morphology, surface roughness, crystalline structure, and orientation of the nanoparticles deposed on silicon substrate were characterized by atomic force microscopy and x-ray diffraction, respectively.