锌锰掺杂Fe3O4纳米颗粒的尺寸可控合成

锌锰掺杂的Fe₃O₄纳米颗粒具有优异的磁性能, 在生物医药领域有广泛的应用前景。磁性纳米颗粒的尺寸与其磁学性质以及生物磁性应用密切相关。因此, 为了适应不同生物应用对尺寸的需求, 研究其尺寸调控具有重要的意义。在本研究中, 我们采用高温热分解法, 通过加入还原剂1,2-十六烷二醇, 改变金属前躯体和回流时间成功制备了尺寸在5~20 nm的锌锰掺杂Fe₃O₄纳米颗粒。研究发现:强还原剂1,2-十六烷二醇的加入有利于合成小尺寸的纳米颗粒, 而以金属氯化物作为金属前躯体和延长回流时间可以进一步合成更大尺寸的纳米颗粒; 纳米颗粒的饱和磁化强度随着尺寸的增大而增大。     

高温多元醇法制备超顺磁CoFe2O4纳米颗粒磁共振造影剂

以FeCl₃·6H₂O、CoCl₂·6H₂O和HOOC-PEG-COOH为反应物, 利用高温多元醇法制备了核心粒径为5~10nm的超顺磁CoFe₂O₄纳米颗粒, 样品在水溶液中具有良好分散性. 通过改变修饰剂的种类和用量、反应温度及反应时间可以对纳米颗粒的尺寸、水中分散性及磁性能产生影响. 研究表明：选用带有强极性基团的修饰剂, 增加修饰剂的用量, 提高反应温度和延长反应时间, 可以增大颗粒的尺寸, 改善颗粒的分散性, 窄化粒径分布. 实验获得的最佳生长条件为：金属盐总量与修饰剂质量比为1∶10, 在210~220℃之间反应2h. 磁性能研究表明所得样品在室温下具有超顺磁性, 其饱和磁化强度与尺寸有关.     

Polyol Synthesis of Fe3 O 4@Tween20 Nanocomposite in Vaseline Oil

For the synthesis of Fe₃O₄@Tween20 nanocomposite, two surfactants (Tween20 and oleic acid) were used to overcome the aggregation. The nanoparticles were used to prepare a water-based Fe₃O₄@Tween20 nanocomposite using oleic acid and Tween20 as surfactants ( Fe₃O₄ colloidal superparticles were developed by introducing Tween20 as a surface modification agent to maintain the colloidal stability of the F e ₃O₄ superparamagnetic nanoparticles (SPION)). Vaseline and the synthesized iron oleate were used for the polyol synthesis of Fe₃O₄@Tween20 nanocomposite. The product has superparamagnetic property. Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA) proved the presence of both surfactants on the surface of the Fe₃O₄ nanoparticles. The product may have potential use in magnetic resonance imaging and hyperthermia.     

溶剂热法合成有机物包裹的钴纳米粒子及其表征

在多元醇媒介中采用溶剂热法合成了油酸/三苯基膦包裹的钴纳米粒子.采用X射线衍射4g(XRD)、透射电镜(TEM)、红外光谱仪(IR)和热重分析仪(TG)对所得样品进行了分析.TEM照片显示所制备的钴纳米粒子粒径约为14nm,分散良好,尺寸分布较窄.XRD分析表明,钴纳米以六角密堆积和面心立方的混晶形式存在.研究发现溶液的pH值对产物有重要影响,即只有当溶液的pH值高于12.62时才可以得到纯的纳米钴.热重分析证实包裹在纳米钴表面的油酸和三本基膦分别占整个纳米粒子质量的25.8%和69.2%.     

Polyetheramide Templated Synthesis of Monodisperse Mn3O4 Nanoparticles with Controlled Size and Study of the Electrochemical Properties

Nano-Micro Letters - Monodisperse Mn3O4 nanoparticles were prepared solvothermally starting from manganese acetate by using polyether amide block copolymers (Pebax2533) as a template in...     

Synthesis and Magnetic Properties of Fe3O4 Nanoparticles

Magnetic Fe₃O₄ nanoparticles with size below 10 nm have been prepared by the aqueous phase coprecipitation method. The Fe₃O₄ nanoparticles show typical superparamagnetism. Comparison is made between the dispersed sample and the powder sample, and the results are discussed.     

Hydrothermal Synthesis and Characterization of PEG Stabilized Co3O4 nanoparticles

Polyethylene glycol stabilized Cobalt oxide, (Co₃O₄), nanoparticles were prepared via simple, one-step, inexpensive hydrothermal method. In this process, polyethylene glycol was used as a solvent and surfactant; gaseous NH₃ was used as an alkalinity additive. Investigation of the structural, morphological, thermal, and magnetic properties were carried out using X-ray diffraction (XRD), infrared spectroscopy (FT-IR), transmission electron spectroscopy (TEM), thermal analysis (TGA), and vibrating sample magnetometer (VSM), respectively. The nanocrystalline nature of the sample was confirmed by XRD and TEM. FT-IR measurement revealed that the O from C?CO coordinates with the surface of Co₃O₄ NP??s. Room temperature VSM measurement showed the ferromagnetic behavior of the product.     

Mn3O4 Nanoparticle Synthesis via Ionic Liquid-Assisted Route

Via the green chemistry route, a new class of Mn₃O₄ nanoparticles has been synthesized using 1-n-butyl-3-methylimidazolium trifluoromethane sulfonate [BMIM][TfO] ionic liquid, which serves as a capping agent. The thermal behavior, phase structure, morphology, and magnetic properties of the samples are characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Field emission scanning electron microscopy (FE-SEM), and Vibrating sample magnetometer (VSM) studies. The phase-pure Mn₃O₄ nanocrystals with 40-nm narrow particle size distribution are obtained with the significant influence of ionic liquid. The synthesized Mn₃O₄ nanoparticles show the superparamagnetic behavior.     

A Green Chemical Synthesis and Characterization of Mn3O4 nanoparticles

Mn₃O₄ nanoparticles were synthesized via an ionic liquid (IL) assisted process at room temperature, which is rather difficult to achieve by other techniques. The synthesized product was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, thermal gravimetry (TG), and vibrating sample magnetometry (VSM). The prepared material showed a high purity, while crystallite size and particle size agree well with each other, 17±2 and 19±3?nm, respectively, revealing nearly single crystalline character of nanoparticles. The product contains 4?wt% of adsorbed water and ionic liquid. This method provides a facile, one-step, and low-cost route for the synthesis of nanostructures of metal oxides. In addition, [BMIM]BF₄ could be collected and reused for subsequent reactions.     

Fe3O4磁性纳米颗粒的合成与接枝聚合修饰（英文）

以氨水作为沉淀剂并控制溶液的pH值,采用Fe3+和Fe2+共沉淀法制得了磁性四氧化三铁纳米颗粒。合成的磁性纳米颗粒通过高分辨透射电镜、X射线衍射仪、傅里叶变换红外光谱仪进行了表征。四氧化三铁纳米颗粒的粒径约为10nm,其表面含有丰富的羟基。为了增强磁性四氧化三铁纳米颗粒和聚合物基质之间的相互作用,在纳米颗粒的表面接枝上乙烯基单体。傅里叶变换红外光谱仪和热重分析仪的测试结果显示,聚合物链共价结合在纳米颗粒表面。表面接枝聚合后,四氧化三铁纳米颗粒由极性转变为非极性。     

超顺磁单分散性Fe3O4磁纳米粒的制备及性能表征

具有超顺磁单分散性的Fe₃O₄磁纳米粒在生物医学材料领域有着广泛的用途. 本研究在水、乙醇和甲苯混合体系74℃回流的条件下制备了具有超顺磁性的表面含油酸的Fe₃O₄磁纳米粒,研究了制备过程中OH^-浓度的变化对磁纳米粒的表面性能、粒径、分散性及磁性能的影响, 并对其机理进行了初步探讨. 采用XRD、FTIR、DLS、TEM和VSM等手段对制备的磁纳米粒进行表征. 结果表明, 当NaOH/Fe(Ⅱ)摩尔比＜8时, Fe₃O₄磁纳米粒表面含油酸可良好地分散于非极性溶剂中, NaOH的加入对磁纳米粒的粒径和饱和磁化强度等性能无明显影响;而当NaOH/Fe(Ⅱ)摩尔比≥8时, Fe₃O₄磁纳米粒仅能分散于水等极性溶剂中, 饱和磁化强度虽可增至40A·m²/kg, 但为多分散且易团聚.     

磁性Fe3O4纳米颗粒的可控制备及生长研究

采用热法合成磁性Fe3O4纳米颗粒,通过精细调控实验条件能对其形状和大小进行有效控制。采用X射线衍射仪、透射电镜、振动样品磁强计等对Fe3O4纳米颗粒的成分、形貌及磁性等进行了表征测试。结果表明,Fe3O4纳米颗粒的饱和磁化强度为62.5emu/g。最后探讨了Fe3O4纳米颗粒的合成机理。     

Mn3O4@ZnO核壳结构纳米片阵列的可控合成及其在水系锌离子电池中的应用

锰基氧化物是一类非常有潜力的水系锌离子电池正极材料, 但是在充放电循环过程中面临结构坍塌而导致容量快速衰减。本研究结合微波水热法和原子层沉积法在碳布上构筑了具有核壳结构的Mn₃O₄@ZnO纳米片阵列, 经优化ZnO的包覆厚度后, Mn₃O₄充放电100个循环的容量保持率可以提高至60.3%。ZnO包覆层可以有效维持Mn₃O₄的结构稳定性, 并且避免其与电解液直接接触而被腐蚀溶解, 从而改善材料的储锌电化学性能。这种核壳状结构的设计为发展高性能水系锌离子电池锰基氧化物正极材料提供了一种有效的思路。     

一步合成Mn3O4@RGO复合材料及其非对称超级电容器的应用

在乙醇胺和水组成的混合溶剂中, Mn(Ac)₂与氧化石墨烯一步反应得到还原石墨烯(RGO)与黑锰矿纳米颗粒(Mn₃O₄)组成的复合材料Mn₃O₄@RGO。以Mn₃O₄@RGO为正极, RGO为负极, 组装得到了具有优良储能性能的非对称型超级电容器Mn₃O₄@RGO//RGO。基于活性物质的总质量, 电容器的最大能量密度可达21.7 Wh/kg, 相应的功率密度为0.5 kW/kg; 同时, 最大功率密度为8 kW/kg时, 对应的能量密度为11.1 Wh/kg。Mn₃O₄@RGO//RGO还表现出良好的循环稳定性, 在经历5000次循环后, 比电容依然保持88.4%。电容器的良好储能性能可归因于在RGO表面生长的高密度Mn₃O₄纳米颗粒和RGO的良好导电性能。