Park Sung Soo, Chu Sang-Wook, Shi Liyi, Yuan Shuai, Ha Chang-Sik
Department of Polymer Science and Engineering, School of Chemical Engineering, Pusan National University, Busan 46241, Korea.
Research Center of Nanoscience and Nanotechnology, Shanghai University, Shanghai 200444, China.
Materials (Basel). 2021 Sep 13;14(18):5270. doi: 10.3390/ma14185270.
Crystalline walled SBA-15 with large pore size were prepared using alkali and alkali earth metal ions (Na, Li, K and Ca). For this work, the ratios of alkali metal ions (Si/metal ion) ranged from 2.1 to 80, while the temperatures tested ranged from 500 to 700 °C. The SBA-15 prepared with Si/Na ratios ranging from 2.1 to 40 at 700 °C exhibited both cristobalite and quartz SiO structures in pore walls. When the Na amount increased (i.e., Si/Na increased from 80 to 40), the pore size was increased remarkably but the surface area and pore volume of the metal ion-based SBA-15 were decreased. When the SBA-15 prepared with Li, K and Ca ions (Si/metal ion = 40) was thermally treated at 700 °C, the crystalline SiO of quartz structure with large pore diameter (i.e., 802.5 Å) was observed for Ca ion-based SBA-15, while no crystalline SiO structures were observed in pore walls for both the K and Li ions treated SBA-15. The crystalline SiO structures may be formed by the rearrangement of silica matrix when alkali or alkali earth metal ions are inserted into silica matrix at elevated temperature.
使用碱金属和碱土金属离子（钠、锂、钾和钙）制备了具有大孔径的晶壁SBA - 15。在这项工作中，碱金属离子的比例（硅/金属离子）范围为2.1至80，而测试温度范围为500至700°C。在700°C下用硅/钠比例范围为2.1至40制备的SBA - 15在孔壁中呈现出方石英和石英SiO结构。当钠含量增加时（即硅/钠从80增加到40），孔径显著增加，但基于金属离子的SBA - 15的表面积和孔体积减小。当用锂、钾和钙离子（硅/金属离子 = 40）制备的SBA - 15在700°C下进行热处理时，基于钙离子的SBA - 15在孔壁中观察到具有大孔径（即802.5 Å）的石英结构的结晶SiO，而对于经钾和锂离子处理的SBA - 15，在孔壁中未观察到结晶SiO结构。当碱金属或碱土金属离子在高温下插入二氧化硅基质中时，结晶SiO结构可能由二氧化硅基质的重排形成。
