Preparation of Fe_3O_4/Mn OOH core–shell nanoparticles by a high-frequency impinging stream reactor  

高频率撞击流反应器制备Fe_3O_4/MnOOH核壳纳米颗粒（英文）

作　　者：王东光 竺柏康 陶亨聪 

机构地区：[1]Petrochemical & Energy Engineering School, Zhejiang Ocean University

出　　处：《Chinese Journal of Chemical Engineering》2015年第4期727-735,共9页中国化学工程学报（英文版）

基　　金：Supported by the National Key Technology R&D Program of China(2009BAB47B08);the Key Science and Technology Project of Zhejiang Province(2008C03006);the Education Office Project of Zhejiang Province(Y201225412);the Technical Innovation League Project of Zhejiang Province for Seawater Desalination(2011LM301)

摘　　要：Well-defined Fe3O4/Mn OOH nanoparticles with 61.1 emu·g-1in magnetization intensity and 90.53 m2·g-1in surface area have been synthesized by a new-style of high-frequency impinging stream(HFIS)reactor.In this reactor,two streams first collided together to form nano Fe3O4suspension,which subsequently flew through an S-shaped main channel to generate high-frequency reversing high-gravity fields.At the same time,24 thin liquid sheets impinged into the main channel at the frequencies higher than 100 Hz to create nano Fe3O4/Mn OOH colloids.The obtained powders were characterized by transmission electron microscopy/energy dispersive spectrometer(TEM/EDS),X-ray diffraction(XRD),Brunner–Emmet–Teller(BET)and vibrating sample magnetometer(VSM).Experimental results indicated that low coating ratio prolonged the induction period of heterogeneous nucleation.The high-frequency impingements of 24 thin liquid sheets greatly accelerated the macro-mixing and the initial dispersion.The high-frequency reversing high-gravity fields promoted the mesoand micro-mixing.As a result,nano Fe3O4cores were fleetly and uniformly covered by Mn OOH precursor.As a continuously operated and static high-gravity reactor,the high-frequency impinging stream(HFIS)reactor is being developed to the large-scaled and low-cost production of various nanocomposites.Well-defined Fe3O4/MnOOHnanoparticleswith61.1 emu·g -1 in magnetization intensity and 90.53 m2·g -1 in surface area have been synthesized by a new-style of high-frequency impinging stream （HFIS） reactor. In this reactor, two streams first collided together to form nano Fe3O4 suspension, which subsequently flew through an S-shaped main channel to generate high-frequency reversing high-gravity fields. At the same time, 24 thin liquid sheets impinged into the main channel at the frequencies higher than 100 Hz to create nano Fe3O4/ MnOOH colloids. The obtained powders were characterized by transmission electron microscopy/energy dispersive spectrometer （TEM/EDS）, X-ray diffraction （XRD）, Brunner-Emmet-Teller （BET） and vibrating sample magnetometer （VSM）. Experimental results indicated that low coating ratio prolonged the induction period of heterogeneous nucleation. The high-frequency impingements of 24 thin liquid sheets greatly accelerated the macro-mixing and the initial dispersion. The high-frequency reversing high-gravity fields promoted the meso- and micro-mixing. As a result, nano Fe3O4 cores were fleetly and uniformly covered by MnOOH precursor. As a continuously operated and static high-gravity reactor, the high-frequency impinging stream （HFIS） reactor is being developed to the large-scaled and low-cost production of various nanocomposites.

关 键 词：High-gravityImpinging streamsMulti-scale mixingsFilm-coatingNanocomposite 

分 类 号：O611.4[理学—无机化学] TB383.1[理学—化学]