镍掺杂三聚氰胺-甲醛气凝胶的浸渍-还原法制备

以PdCl2为活化敏化液,水合肼为还原剂,采用化学浸渍-还原法在常温下制得了磁性金属Ni掺杂三聚氰胺-甲醛（MF）气凝胶,为金属掺杂气凝胶的制备寻得了新的途径。利用X-射线粉末衍射仪（XRD）、扫描电镜（SEM）、透射电镜（TEM）等对Ni掺杂MF气凝胶进行表征,SEM和TEM均表明,经浸渍-还原处理后的MF气凝胶骨架中较均匀地分布着粒径约100 nm的金属Ni颗粒,其中部分颗粒生长连结形成较大团簇。N2吸-脱附实验数据显示,掺入金属Ni后,MF气凝胶的比表面积、总孔体积、微孔体积均减小,表明浸渍-还原处理后得到的金属Ni颗粒均匀分布于MF气凝胶孔隙中,其中少量大孔的出现是由形成团簇的Ni颗粒填充了部分纯MF气凝胶的孔隙撑开了孔隙结构所致。

Preparation of Ni-doped melamine-formaldehyde aerogels by impregnation-reduction method

Ni-doped MF(melamine-formaldehyde) aerogels are prepared through impregnation-reduction with the hydrazinium hydroxide(80%, AR) as the reducing agent after MF aerogels being activated by PdCl2. Both the Scanning Electron Microscope(SEM) and the Transmission Electron Microscope (TEM) images demonstrate that there are a great deal of Ni particles with a size of 100nm existing in the framework of MF aerogels. Meanwhile, a small part of clusters is observed in the SEM and TEM images. The nitrogen adsorption-desorption data show that the specific surface area, total pore volume and micropore volume of MF aerogels all decrease after Ni doping. Moreover, a small amount of macropore is produced by large size Ni particle clusters, further confirming that the nanochannels of MF aerogels are filled with Ni.