Kuśtrowski Piotr, Chmielarz Lucjan, Dziembaj Roman, Cool Pegie, Vansant Etienne F
Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland.
J Phys Chem B. 2005 Jun 16;109(23):11552-8. doi: 10.1021/jp050696o.
Four various mesoporous silicas (MCM-48, SBA-15, MCF, and MSU) were modified by the molecular designed dispersion method using Fe(acac)3, Cr(acac)3, and Cu(acac)2 complexes. The deposition was performed at the same concentration of the metal acetylacetonate (acac) complex in a toluene solution. All as-synthesized samples were investigated by diffuse reflectance infrared Fourier transform spectroscopy, Fourier transform infrared photoacoustic spectroscopy, and thermogravimetric analysis. The calcined materials were studied with respect to their textural properties (Brunauer-Emmett-Teller adsorption isotherm) and chemical composition (electron microprobe analysis). It allowed elucidation of the mechanism of interaction between the acac complex and the silanol groups. For the MCM-48, SBA-15, and MCF materials, the formation of hydrogen bonding was found for the chromium- and copper-modified samples, whereas the Fe-containing materials showed the ligand exchange mechanism. The strong interaction of the MSU support and the different acetylacetonate complexes, resulting in a loss of at least one acac ligand, was observed. The mesoporous silicas modified with transition metal oxides were studied by UV-vis-DR spectroscopy. The different metal dispersions were found for the samples containing various transition metal oxides.
采用分子设计分散法，用乙酰丙酮铁（Fe(acac)3）、乙酰丙酮铬（Cr(acac)3）和乙酰丙酮铜（Cu(acac)2）配合物对四种不同的介孔二氧化硅（MCM - 48、SBA - 15、MCF和MSU）进行了改性。沉积过程在甲苯溶液中以相同浓度的金属乙酰丙酮（acac）配合物进行。通过漫反射红外傅里叶变换光谱、傅里叶变换红外光声光谱和热重分析对所有合成样品进行了研究。对煅烧后的材料进行了结构性质（布鲁诺尔 - 埃米特 - 泰勒吸附等温线）和化学成分（电子微探针分析）的研究。这有助于阐明acac配合物与硅醇基团之间的相互作用机制。对于MCM - 48、SBA - 15和MCF材料，在铬和铜改性的样品中发现了氢键的形成，而含铁材料显示出配体交换机制。观察到MSU载体与不同的乙酰丙酮配合物之间有强烈的相互作用，导致至少一个acac配体的损失。通过紫外 - 可见 - 漫反射光谱对用过渡金属氧化物改性的介孔二氧化硅进行了研究。在含有各种过渡金属氧化物的样品中发现了不同的金属分散情况。
