三维有序大孔SiW12/SiO2杂化材料的制备及表征

 用自然沉降法组装成规则排列的聚苯乙烯胶晶,并以此作为模板剂,用Keggin结构的杂多酸SiW12和正硅酸乙酯组成溶胶作为先驱物,成功制备了三维有序大孔(3DOM)SiW12/SiO2杂化材料. XRD和IR等测试结果表明,所得样品中的杂多酸SiW12能够保持其Keggin结构,SEM观察显示,样品具有三维大孔规则排列的结构. 研究发现,溶胶组成对杂化材料的3DOM结构影响很大,纯SiW12难以形成3DOM结构,随着SiO2含量的增加,样品的孔结构三维规整性和强度明显增强,而且引入SiO2可有效提高杂多酸的热稳定性.

Synthesis and Characterization of Three-Dimensional Ordered Macroporous SiW12/SiO2 Hybrid Materials

Three-dimensional ordered macroporous(3DOM) SiW_(12)/SiO_2 hybrid materials were synthesized by using Keggin-type heteropolyacid SiW_(12) and tetraethyl orthosilicate(TEOS) as raw materials and polystyrene colloidal crystal assembled by sedimentation as template.The properties and structures of the hybrid materials were determined by FT-IR,XRD,SEM and DTA.It was difficult to form 3DOM material by using heteropolyacid SiW_(12) only.But the 3DOM structure could be formed and the strength of the samples was significantly improved by the addition of SiO_2 to SiW_(12),while the heteropolyacid SiW_(12) maintained its Keggin structure in these SiW_(12)/SiO_2 hybrid materials.Moreover,the thermal stability of SiW_(12) also increased obviously.The study indicated that the 3DOM SiW_(12)/SiO_2 hybrid materials with Keggin-type heterpolyacid could be successfully synthesized according to the process provided in present article.