摘要
通过后合成修饰方法(PSM)构筑了空心纳米球(Void@UiO-66-Ⅰ)和实心块(UiO-66-Ⅰ)2种形貌的季铵盐功能化UiO-66-NH_2(Zr),得到兼具酸碱活性位点和氢键给体的新型功能化金属-有机框架材料.通过一系列表征证明2种催化剂的成功合成,并将它们用于催化转化CO_(2)和氧化苯乙烯的环加成反应.由于Void@UiO-66-Ⅰ催化剂的季铵盐部分含有大量的羟基和卤素阴离子,可以通过氢键和亲核攻击与环氧化合物连接,诱导环氧化合物开环,促使反应顺利进行,且催化剂的中空结构有利于物质进出催化剂,起到加快反应速率的作用,使得该催化剂在CO_(2)与氧化苯乙烯环加成反应中表现出比实心块UiO-66-Ⅰ催化剂更好的催化性能.Void@UiO-66-Ⅰ催化剂在120℃,CO_(2)压力为1.2 MPa,反应时间为6 h,无溶剂和助催化剂的反应条件下,碳酸苯乙烯酯的收率和选择性分别为85.5%和95%.
Hollow nanosphere Void@UiO-66-Ⅰand bulk UiO-66-Ⅰwere designed and prepared by post-synthetic modification(PSM)technique.Such two Zr-MOFs functionalized by quaternary ammonium salt possessed acid-base active sites and hydrogen bond donors.A series of characterization results demonstrated that the two catalysts were successfully synthesized and could be used to catalyze the cycloaddition reaction of CO_(2)and styrene oxide.Due to the quaternary ammonium salt of Void@UiO-66-Ⅰwith a large number of hydro-xyl groups and halogen anion,it could induce the epoxide ring-opening by hydrogen bond and nucleophilic attack of the iodide,promoting the reaction proceed smoothly.Moreover,the hollow structure of Void@UiO-66-Ⅰwas conducive to the mass transport.Therefore,it showed better catalytic performance than bulk UiO-66-Ⅰcatalyst for the reaction of CO_(2)and styrene oxide cycloaddition.Under optimal reaction conditions(120℃,initial CO_(2)pressure 1.2 MPa,6 h),without solvent and co-catalyst,the yield and selectivity of styrene carbonate(SC)were 85.5%and 95.2%,respectively.
作者
李美燕
陈紫娟
汪淑华
陈超
LI Meiyan;CHEN Zijuan;WANG Shuhua;CHEN Chao(Key Laboratory of Jiangxi Province for Environment and Energy Catalysis,College of Chemistry,Nanchang University,Nanchang 330031,China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2021年第8期2474-2482,共9页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21961021,21661020)
江西省自然科学基金重点项目(批准号:20202ACB203001)资助。
关键词
UiO-66
纳米空心球
季铵盐
后合成修饰
二氧化碳环加成
UiO-66
Hollow nanospheres
Quaternary ammonium salt
Post-synthetic modification
CO_(2)cycloaddition reaction
