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Synthesis of Poly(methacrylic acid)-MnO(OH)2/SiO2 Core-shell and the Corresponding Hollow Microspheres Containing Mn2O3
作者:Shuxuan Sun, Bin Liu, Xiaomeng Fu, Meijun Zhou, Guomin Bian, Yonglin Qi, and Xinlin Yang*,
關(guān)鍵字:Polymer/inorganic core-shell microsphere; Mn2O3/m-SiO2 double-shelled hollow microsphere; Braunite-1Q hollow microsphere; Mn2O3 hollow microsphere.
論文來(lái)源:期刊
具體來(lái)源:J Colloid Interface Sci, 438 (1), 269-276 (2015).
發(fā)表時(shí)間:2015年

Poly(methacrylic acid)-MnO(OH)2/SiO2 core-shell microspheres were prepared by the sol-gel hydrolysis of tetraethylorthosilicate (TEOS) in presence of poly(methacrylic acid)-Mn(II) (PMAA-Mn2+) as template with ammonium hydroxide anion as the catalyst and n-octadecyltrimethoxysilane (C18TMS) as pore-directing reagent. The PMAA-Mn2+ core was prepared by incubation of Mn2+ cations with PMAA microspheres via the coordination between the carboxylate anion group on PMAA microsphere and Mn2+ cations. During this process, the Mn(II) specie were formed as white Mn(OH)2 at first and it was subsequently oxidized into brown MnO(OH)2 in air. The Mn2O3/mesoporous silica (Mn2O3/m-SiO2) double-shelled hollow microspheres (DSHMs) were prepared through the calcination of the PMAA-MnO(OH)2/SiO2 core-shell microspheres at 600 oC for selective removal of the PMAA template and the pore-directing organic component from C18TMS, in which the crystalline structure of DSHM was developed into Braunite-1Q via the reaction between Mn2O3 inner-shell and silica outer-shell by annealing the DSHMs under higher temperatures of 800 and 900 oC. The Mn2O3 hollow microspheres (HMs) were prepared through the selective removal of the silica layer from the DSHMs by sodium hydroxide aqueous solution, which exhibited structure integrity and good ethanol dispersity due to presence of mesoporous structure.