稀有金属材料与工程
稀有金屬材料與工程
희유금속재료여공정
RARE METAL MATERIALS AND ENGINEERNG
2009年
z2期
373-376
,共4页
黄飞%傅正义%贾铁昆%王为民
黃飛%傅正義%賈鐵昆%王為民
황비%부정의%가철곤%왕위민
介孔氧化硅%甲醇%微结构%形貌
介孔氧化硅%甲醇%微結構%形貌
개공양화규%갑순%미결구%형모
mesoporous silica%methanol%microstructure%morphology
以三嵌段共聚物P123为模板剂、正硅酸乙酯TEOS为无机硅源,采用水热法合成了SBA-15介孔分子筛,并采用XRD、SEM、TEM、N_2吸附-脱附等表征手段研究了不同含量的甲醇对SBA-15分子筛的结构与形貌的影响.结果表明:甲醇对SBA-15介孔材料的形貌与结构影响较大,随着甲醇含量的增加,SBA-15介孔分子筛逐渐从纤维状变为球形,且在很宽的浓度范围内存在一个纤维状与球形共存的中间态,这主要是由于亲水性小分子的嵌入导致双胶束的形成,并最终形成两种形貌的共存;同时,随着甲醇含量的增加,介孔由有序向无序状态变化,N_2吸附-脱附实验表明平均孔径逐渐从10.2 nm降低到8.8 nm,孔径的分布逐渐变宽,孔容由1.003 cm~3/g逐渐增加到2.708 cm~3/g,比表面积由455.3 m~2/g增加到1063 m~2/g,说明随着甲醇添加量的增加,介孔逐渐向微孔方向扩展.
以三嵌段共聚物P123為模闆劑、正硅痠乙酯TEOS為無機硅源,採用水熱法閤成瞭SBA-15介孔分子篩,併採用XRD、SEM、TEM、N_2吸附-脫附等錶徵手段研究瞭不同含量的甲醇對SBA-15分子篩的結構與形貌的影響.結果錶明:甲醇對SBA-15介孔材料的形貌與結構影響較大,隨著甲醇含量的增加,SBA-15介孔分子篩逐漸從纖維狀變為毬形,且在很寬的濃度範圍內存在一箇纖維狀與毬形共存的中間態,這主要是由于親水性小分子的嵌入導緻雙膠束的形成,併最終形成兩種形貌的共存;同時,隨著甲醇含量的增加,介孔由有序嚮無序狀態變化,N_2吸附-脫附實驗錶明平均孔徑逐漸從10.2 nm降低到8.8 nm,孔徑的分佈逐漸變寬,孔容由1.003 cm~3/g逐漸增加到2.708 cm~3/g,比錶麵積由455.3 m~2/g增加到1063 m~2/g,說明隨著甲醇添加量的增加,介孔逐漸嚮微孔方嚮擴展.
이삼감단공취물P123위모판제、정규산을지TEOS위무궤규원,채용수열법합성료SBA-15개공분자사,병채용XRD、SEM、TEM、N_2흡부-탈부등표정수단연구료불동함량적갑순대SBA-15분자사적결구여형모적영향.결과표명:갑순대SBA-15개공재료적형모여결구영향교대,수착갑순함량적증가,SBA-15개공분자사축점종섬유상변위구형,차재흔관적농도범위내존재일개섬유상여구형공존적중간태,저주요시유우친수성소분자적감입도치쌍효속적형성,병최종형성량충형모적공존;동시,수착갑순함량적증가,개공유유서향무서상태변화,N_2흡부-탈부실험표명평균공경축점종10.2 nm강저도8.8 nm,공경적분포축점변관,공용유1.003 cm~3/g축점증가도2.708 cm~3/g,비표면적유455.3 m~2/g증가도1063 m~2/g,설명수착갑순첨가량적증가,개공축점향미공방향확전.
Ordered mesoporous molecular sieve SBA-15 was synthesized by hydrothermal reaction with TEOS as the source of inorganic silica and triblock copolymer P123 as the template in strong acid media. Microstructure and morphology of the sample were characterized by XRD, SEM, TEM and N_2 adsorption/desorption isotherm. The results show that the fibre was gradually evolved to sphere in a wide range of concentration of P123 surfactant and formed coexistence of two morphologies when methanol was added to the solution, which resulted from embedding of small molecules methanol. N_2 adsorption/desorption shows that average pore size decreases from 10.2 nm to 8.8 nm, however, pore volume and surface area increase from 1.003 to 2.708 cm~3/g and from 455.3 to 1063 m~2/g, respectively, indicating that the increase of micropores.