铜掺杂SBA-15的pH调节法直接合成及其在N_2O分解反应中的催化性能(英文)

Copper Containing SBA-15 Prepared through pH Modification Method and Its Catalytic Activity for N_2 O Decomposition

酸性条件下,用环六亚甲基四胺作为pH调节剂,采用pH调节法直接合成了铜同构替代掺杂的SBA-15中孔分子筛(Cu/SBA-15).采用X-射线衍射(XRD)、扫描电子显微镜-能量色散X射线光谱(SEM-EDX)、透射电子显微镜(TEM)以及傅立叶变换红外光谱(FT-IR)等技术对目标材料进行了表征.结果表明:该材料具有六方中孔有序结构,且环六亚甲基四胺显著影响了铜和SBA-15硅骨架的结合,在水热合成过程中,环六亚甲基四胺分解释放出氨气,增加了体系的pH值,有助于更多的铜进入到分子筛的骨架中.该材料可用于N2O分解反应的催化剂,其中Cu/SBA-15(110)在600℃下具有优异的催化活性,可分解50%N2O.

Copper-substituted SBA-15（Cu/SBA-15） mesoporous materials were directly synthesized under acidic conditions by a ＂pH modification method＂ using hexamethylenetetramine（HMTA） as an internal pH-modifier.The synthesized material has been characterized by XRD,SEM-EDX,TEM and FT-IR.The results showed that the resultant materials exhibit highly ordered hexagonal mesoporous structures.In addition,the HMTA also strongly affected the incorporation of copper in the silica framework.During hydrothermal process the HMTA dissociates to release NH3 and increases the internal pH value and helps to introduce more copper into SBA-15 framework.Catalytic screenings reveal that Cu/SBA-15 materials can be used as potential catalyst for the decomposition of N2O.The Cu/SBA-15（110） have good catalytic activity causing 50% of N2O to decomposed at 600°C.