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直接在介孔SiO_2中掺杂金属Zr不是十分容易,这主要是由于在强酸介质中,Zr往往不能与Si源一起共缩合而被沉积到介孔SiO_2骨架中。因此,本文采用原位一步合成法,在含有模板剂、盐酸、醋酸锌的弱酸性水溶液中添加Si源和Zr源,通过原位共沉积,直接制备出具有介孔结构的Zr-SiO_2材料。研究结果表明:当合成母液中Zr与Si的摩尔比r≤0.2∶1时,所得样品具有高度有序的介孔结构;继续增加Zr的添加量(r=0.3或0.5)会使有序孔的规整性下降。随着合成体系中r从0.01变化到0.2,样品晶胞参数由9.7nm增加到10.9nm,孔壁厚度由1.4nm增大到2.6nm,证明了Zr对介孔SiO_2骨架的有效掺杂。通过改变样品中的Zr掺杂量还可以调控所得Zr-SiO_2材料的形貌,获得具有蠕虫状、葡萄状和麦粒状等形状规整的粒子。介孔Zr-SiO_2材料在去除水体中有机染料亚甲基蓝中表现出良好的性能。
The direct doping of mesoporous SiO 2 with Zr is not very easy, which is mainly due to the fact that Zr can not be co-condensed with Si source and is deposited into the mesoporous SiO 2 skeleton in strong acid medium. Therefore, in this paper, a Si-source and a Zr source were added into the weak acidic aqueous solution containing template agent, hydrochloric acid and zinc acetate by in-situ one-step synthesis method to prepare Zr-SiO 2 material with mesoporous structure by in-situ co-deposition. The results show that when the molar ratio of Zr to Si in the synthesis mother liquor is less than or equal to 0.2: 1, the resulting sample has a highly ordered mesoporous structure. Continuing to increase the addition of Zr (r = 0.3 or 0.5) The regularity drops. With the change of r from 0.01 to 0.2 in the synthesis system, the unit cell parameters increase from 9.7 nm to 10.9 nm and the wall thickness increases from 1.4 nm to 2.6 nm, which proves that Zr effectively doping mesoporous SiO 2 framework. By changing the amount of Zr doping in the sample, the morphology of the obtained Zr-SiO 2 material can also be controlled to obtain particles with regular shape such as worm-like, grape-like and wheat-like. The mesoporous Zr-SiO 2 material has good performance in removing organic dye methylene blue from water.