钒氧化物微/纳米空心球制备技术的研究

钒氧化物微/纳米空心球由于具有比表面积高、负载容量大、密度低等特性,在催化剂、传感器、锂离子电池、电池阴极材料等相关行业中有着广泛的应用前景和研究价值。本文综述了钒氧化物微/纳米空心球材料的制备方法,包括软模板剂法、硬模板剂法、水热合成法和溶剂热合成法等的研究进展,并对今后的研究方向进行了展望。     

钒氧化物微/纳米空心球的制备技术的研究

钒氧化物微/纳米空心球由于具有比表面积高、负载容量大、密度低等特性,在催化剂、传感器、锂离子电池、电池阴极材料等相关行业中有着广泛的应用前景和研究价值。本文综述了钒氧化物微/纳米空心球材料的制备方法(包括软模板剂法、硬模板剂法、水热合成法和溶剂热合成法)及相关研究进展,并对今后的研究方向进行了展望。     

低温催化法制备石墨化碳空心球

石墨化碳空心球因具有密度小、稳定性好和可填充中空结构等特点,受到了研究者的广泛关注。本文结合国内外的研究进展,综述了近年来发展起来的采用过渡金属如铁、钴、镍等为催化剂,低温(<1 000℃)催化法合成石墨化碳空心球的最新研究进展。介绍了低温催化法提高碳空心球石墨化程度的机理,说明了石墨化碳空心球的表征方法,展望了石墨化碳空心球的应用前景。最后指出了相关研究中有待解决的问题。     

模板法合成核壳功能材料

模板法制备核壳功能材料是材料科学研究领域的一大热点引起了广泛的关注.本文结合本课题组在有机-无机核壳复合纳米粒子(空心球)领域的研究,较系统地评述了目前国内外利用模板法制备核壳粒子的研究进展,并概述了核壳纳米粒子(空心球)的发展前景和应用领域.     

获得环境响应聚合物胶束和空心球的途径

概述了本研究组近年来发展的几种制备环境敏感的聚合物纳米胶束和空心球的新方法,包括通过聚合物间的氢键相互作用构建“非共价键合胶束”的自组装方法,将聚合物自组装与单体的原位聚合相结合的方法以及利用接枝共聚物中的主链和支链间的络合作用诱导胶束化和胶束与空心球的可逆转化等.讨论了这些聚合物纳米微球和空心球对温度、pH及离子强度等的响应特性.     

微纳米稀土氯氧化物的合成研究进展

稀土氯氧化物作为一种重要的发光基质,具有较高的光吸收效率和传能效率,在彩色显示、催化、生物医药、光电转换、气敏等领域均有广泛的应用,已成为光功能材料领域的研究热点之一。目前研究者已用固相法、沉淀法、液相-高温焙烧法、水热与溶剂热法、前驱体热解法、溶胶-凝胶法、静电纺丝法等方法成功地制备了稀土氯氧化物微米颗粒,纳米颗粒、纳米条、纳米片、纳米棒、纳米针、纳米纤维、纳米带、纳米管等稀土氯氧化物微纳米材料。总结了各种制备方法的研究进展及优缺点,并结合本课题组在稀土氯氧化物纳米材料方面的研究工作,对稀土氯氧化物微纳米材料的制备方法的发展方向进行了展望。     

碳纳米材料及其在多相催化中的应用

碳纳米材料（包括零维、一维、二维碳纳米材料以及碳纳米孔材料）是一类新型的催化剂或催化剂载体材料,在氧化脱氢、选择加氢、合成氨、氨分解制氢以及燃料电池等多相催化领域具有广阔的应用前景。本文综述了近年来新型碳纳米材料在多相催化领域中的应用研究进展,介绍了这类催化材料的制备方法,重点阐述了碳载体的微/介观结构、掺杂、电子性质、表面性质、限域效应等对所担载的催化活性组分的分散,对反应物的扩散以及对催化反应的活性和选择性等方面的影响。     

以碳微球为核的金纳米壳球体的制备

通过水热合成法制备了单分散碳微球, 并以此单分散碳微球为核, 利用其表面修饰的银纳米粒子作为种子, 进一步还原制备了以碳微球为核、以金为壳的金纳米壳(Nanoshell)球体. 通过透射电子显微镜和紫外可见吸收光谱对其形态以及光谱性质进行了表征. 研究结果表明, 采用该种方法制备出来的碳微球具有良好的单分散性, 表面修饰简便快捷, 利用碳微球为核制备的金纳米壳球体尺寸可控, 在近红外范围内有强吸收. 实验结果证明该方法是制备金纳米壳球体的一种有效新方法.     

聚合物微/纳米纤维膜的研究与应用

近年来聚合物微/纳米纤维膜因具有比表面积大、密度低、孔隙率高、孔间结合性良好、易与纳米尺寸的活性物质结合等系列优异性能而受到越来越多的关注。本文归纳了聚合物微/纳米纤维的制备及其发展;分类介绍了聚合物微/纳米纤维膜的研究进展和表征方法;同时概述了聚合物微/纳米纤维膜应用在过滤材料、医药、组织工程等方面的研究情况。     

管状AgNO_3-Tu配合物的制备

微纳米材料是当今材料研究领域中最富有活力的研究对象之一.空心微纳米材料,如纳米空心球、纳米笼、纳米管等,由于具有特殊的结构和物理化学性能,引起了人们极大的兴趣[1,2].特别是,自从1991年日本NEC公司的Iijmia教授等发现纳米碳管以来,以碳纳米管为代表的管状结构微纳米材料以其独特的中空结构,被应用于药物缓释、流体传输、微反应器、生物催化及分析检测等方面[3,4].     

A Strategy to Synthesize Hollow Micro/Nanospheres with Tunable Shell Thickness

A simple one‐step direct templating method is developed to synthesize hollow carbon and sandwich‐like ZnO/C/ZnO micro/nanospheres. The type and shell thickness of the final products can be controlled by simply adjusting the reaction temperature. The removal of the templates can also be easily controlled during the synthesis. At a low temperature, the templates remain in the products to form hollow sandwich‐like micro/nanospheres. As the reaction temperature rises, the templates are consumed, which results in the preparation of hollow carbon micro/nanospheres. On the basis of a series of experiments, we propose a simple plausible mechanism to address the original strategy for synthesizing these hollow micro/nanospheres. Furthermore, the sandwich‐like ZnO/C/ZnO nanospheres can be used as the anode in lithium‐ion batteries, exhibiting an extraordinary cyclability and a high coulombic efficiency. This approach can be extended to the synthesis of other hollow spheres. Further investigation is underway in our group.     

Radially Inwardly Aligned Hierarchical Porous Carbon for Ultra‐Long‐Life Lithium–Sulfur Batteries

Rational design of hollow micro‐ and/or nano‐structured cathodes as sulfur hosts has potential for high‐performance lithium‐sulfur batteries. However, their further commercial application is hindered because infusing sulfur into hollow hosts is hard to control and the interactions between high loading sulfur and electrolyte are poor. Herein, we designed hierarchical porous hollow carbon nanospheres with radially inwardly aligned supporting ribs to mitigate these problems. Such a structure could aid the sulfur infusion and maximize sulfur utilization owing to the well‐ordered pore channels. This highly organized internal carbon skeleton can also enhance the electronic conductivity. The hollow carbon nanospheres with further nitrogen‐doping as the sulfur host material exhibit good capacity and excellent cycling performance (0.044 % capacity degradation per each cycle for 1000 cycles).     

A novel amperometric biosensor based on NiO hollow nanospheres for biosensing glucose

NiO hollow nanospheres were synthesized by controlled precipitation of metal ions with urea using carbon microspheres as templates, which were for the first time adopted to construct a novel amperometric glucose biosensor. Glucose oxidase was immobilized on the surface of hollow nanospheres through chitosan-assisted cross-linking technique. Due to the high specific active sites and high electrocatalytic activity of NiO hollow nanospheres, the constructed glucose biosensors exhibited a high sensitivity of 3.43 μA/mM. The low detection limit was estimated to be 47 μM (S/N = 3), and the Michaelis-Menten constant was found to be 7.76 mM, indicating the high affinity of enzyme on NiO hollow nanospheres to glucose. These results show that the NiO hollow nanospheres are a promising material to construct enzyme biosensors.     

无机微/纳空心球*

无机微/纳空心球材料以其独特的结构、优异的物理化学性能和广阔的应用前景,成为微/纳米材料研究和开发的一个热点领域之一。到目前为止,已研究开发出若干微/纳空心球材料的制备方法,并已制备出具有特殊物理和化学性能的空心球材料。其中,近年来的相关报道尤其多。本文主要回顾了近年来微/纳空心球材料研究和开发的最新进展,其中包括各种制备方法的原理、优缺点和适用范围,并展望了微/纳空心球材料的应用前景。     

Radially Inwardly Aligned Hierarchical Porous Carbon for Ultra-Long-Life Lithium–Sulfur Batteries

Rational design of hollow micro- and/or nano-structured cathodes as sulfur hosts has potential for high-performance lithium-sulfur batteries. However, their further commercial application is hindered because infusing sulfur into hollow hosts is hard to control and the interactions between high loading sulfur and electrolyte are poor. Herein, we designed hierarchical porous hollow carbon nanospheres with radially inwardly aligned supporting ribs to mitigate these problems. Such a structure could aid the sulfur infusion and maximize sulfur utilization owing to the well-ordered pore channels. This highly organized internal carbon skeleton can also enhance the electronic conductivity. The hollow carbon nanospheres with further nitrogen-doping as the sulfur host material exhibit good capacity and excellent cycling performance (0.044 % capacity degradation per each cycle for 1000 cycles).     

Graphitic carbon nanostructures via a facile microwave-induced solid-state process

A novel approach to fabricate highly graphitic carbon nanostructures such as carbon nanotubes (CNTs), metal/graphitic-shell nanocrystals and hollow carbon nanospheres (HCNSs) in a very short time is demonstrated.     

A general method for the rapid synthesis of hollow metallic or bimetallic nanoelectrocatalysts with urchinlike morphology

We have reported a facile and general method for the rapid synthesis of hollow nanostructures with urchinlike morphology. In-situ produced Ag nanoparticles can be used as sacrificial templates to rapidly synthesize diverse hollow urchinlike metallic or bimetallic (such as Au/Pt) nanostructures. It has been found that heating the solution at 100 degrees C during the galvanic replacement is very necessary for obtaining urchinlike nanostructures. Through changing the molar ratios of Ag to Pt, the wall thickness of hollow nanospheres can be easily controlled; through changing the diameter of Ag nanoparticles, the size of cavity of hollow nanospheres can be facilely controlled; through changing the morphologies of Ag nanostructures from nanoparticle to nanowire, hollow Pt nanotubes can be easily designed. This one-pot approach can be extended to synthesize other hollow nanospheres such as Pd, Pd/Pt, Au/Pd, and Au/Pt. The features of this technique are that it is facile, quick, economical, and versatile. Most importantly, the hollow bimetallic nanospheres (Au/Pt and Pd/Pt) obtained here exhibit an area of greater electrochemical activity than other Pt hollow or solid nanospheres. In addition, the approximately 6 nm hollow urchinlike Pt nanospheres can achieve a potential of up to 0.57 V for oxygen reduction, which is about 200 mV more positive than that obtained by using a approximately 6 nm Pt nanoparticle modified glassy carbon (GC) electrode. Rotating ring-disk electrode (RRDE) voltammetry demonstrates that approximately 6 nm hollow Pt nanospheres can catalyze an almost four-electron reduction of O(2) to H(2)O in air-saturated H(2)SO(4) (0.5 M). Finally, compared to the approximately 6 nm Pt nanoparticle catalyst, the approximately 6 nm hollow urchinlike Pt nanosphere catalyst exhibits a superior electrocatalytic activity toward the methanol oxidation reaction at the same Pt loadings.     

Preparation and properties of nitrogen-containing hollow carbon nanospheres by pyrolysis of polyaniline-lignosulfonate composites

Polyaniline-lignosulfonate composite hollow spheres were synthesized by using one-step unstirred polymerization of aniline in the presence of lignosulfonate. Novel nitrogen-containing hollow carbon nanospheres were prepared by direct pyrolysis of the polyaniline-lignosulfonate composite spheres at different temperatures under a nitrogen atmosphere. Thermal behavior of the polyaniline-lignosulfonate composite spheres was studied by TG-DTG, FTIR and element analyze instruments. The resultant carbon spheres were characterized by SEM, XRD and nitrogen adsorption-desorption measurement. It was found that the pyrolysis products of the polyaniline-lignosulfonate composite spheres were made up of uniform hollow carbon nanospheres with an average diameter of 135 nm. Furthermore, the hollow carbon nanospheres exhibit high BET surface area range from 381.6 m² g⁻¹ to 700.2 m² g⁻¹. The hollow carbon nanospheres could be used as adsorbents of papain. The papain adsorption capacity for the carbon spheres prepared at 1200 °C was up to 1161 mg g⁻¹ at an initial papain concentration of 10 mg mL⁻¹ at 25 °C.     

Facile synthesis of Fe3O4@C hollow nanospheres and their application in polluted water treatment

Nanostructured carbon-based materials, such as carbon nanotube arrays have shown respectable removal ability for heavy metal ions and organic dyes in aqueous solution. Although the carbon-based materials exhibited excellent removal ability, the separation of them from the aqueous solution is difficult and time-consuming. Here we demonstrated a novel and facile route for the large-scale fabrication of Fe₃O₄@C hollow nanospheres, with using ferrocene as a single reagent and SiO₂ as a template. The as-prepared Fe₃O₄@C hollow nanospheres exhibited adsorption ability for heavy metal ions and organic dyes from aqueous solution, and can be easily separated by an external magnet. When the as-prepared Fe₃O₄@C hollow nanospheres were mixed with the aqueous solution of Hg²⁺ within 15 min, the removal efficiency was 90.3%. The as-prepared Fe₃O₄@C hollow nanospheres were also exhibited a high adsorption capacity (100%) as the adsorbent for methylene blue (MB). In addition, the as-prepared Fe₃O₄@C hollow nanospheres can be used as the recyclable sorbent for water treatment via a simple magnetic separation.     

Superior Electrochemical Properties of Nanofibers Composed of Hollow CoFe2O4 Nanospheres Covered with Onion‐Like Graphitic Carbon

Nanofibers composed of hollow CoFe₂O₄ nanospheres covered with onion‐like carbon are prepared by applying nanoscale Kirkendall diffusion to the electrospinning process. Amorphous carbon nanofibers embedded with CoFe₂@onion‐like carbon nanospheres are prepared by reduction of the electrospun nanofibers. Oxidation of the CoFe₂‐C nanofibers at 300 °C under a normal atmosphere produces porous nanofibers composed of hollow CoFe₂O₄ nanospheres covered with onion‐like carbon. CoFe₂ nanocrystals are transformed into the hollow CoFe₂O₄ nanospheres during oxidation through a well‐known nanoscale Kirkendall diffusion process. The discharge capacities of the carbon‐free CoFe₂O₄ nanofibers composed of hollow nanospheres and the nanofibers composed of hollow CoFe₂O₄ nanospheres covered with onion‐like carbon are 340 and 930 mA h g^?1, respectively, for the 1000th cycle at a current density of 1 A g^?1. The nanofibers composed of hollow CoFe₂O₄ nanospheres covered with onion‐like carbon exhibit an excellent rate performance even in the absence of conductive materials.