金属-有机骨架[Cu(INA)_2·H_2O]_n纳米晶的超声制备及其催化性质研究

Ultrasonic Synthesis and Catalytic Properties of Nanocrystals of Metal-Organic Framework [Cu(INA)_2·H_2O]_n

在EtOH/DMF/H2O(2:2:1)的混合溶剂中,以硝酸铜(Cu(NO3)2·3H2O)和异烟酸(HINA)为原料,超声制备了具有三维结构的金属-有机骨架(MOF)[Cu(INA)2·H2O]n纳米晶,并利用粉末X-射线衍射(XRD)、红外光谱(IR)、透射电子显微镜(TEM)等分别对目标产物的结构和形貌进行了表征。研究结果表明,与传统的水热/溶剂热等制备方法相比较,超声制备方法具有合成时间短(5-60min)、反应条件温和(常温常压)和反应产率高(50.9%-60.2%)等优点。相关催化动力学研究表明,所制备MOF纳米晶在乙腈和水的混合溶剂中能够选择性催化氧化苯甲醇为苯甲醛,分别研究了不同的反应温度、催化剂量以及空气流量对催化反应的影响,并初步探讨了催化反应机理。

Nanocrystals of three-dimensional （ 3D ） metal-organic framework （ MOF）, [ Cu （ INA ） 2 H2O] ,（INA = isonicotinic acid） were synthesized by using an ultrasonic method. The reaction of Cu （NO3）2 3H2O] and HINA in a mixed solution of EtOH/DMF/H2O （2： 2： 1, v/v） under ultrasonic irradiation for short reaction times （5 - 60 min） gave [ Cu （INA） 2 H2O ], nanocrystals in high yields （50.9% -60.2% ）. Structure and morphology of the as-synthesized MOF nanocrystals were confirmed by powder X-ray differation （ XRD）, fourier transform infraved spectroscopy （FI-IR） and transmisson electron microscope （TEM） techniques. The results reveal that the MOF nanocrystals could be obtained in high yields under mild conditions （e. g. ambient temperature and pressure） by using the ultrasonic method. MOF nanocrystals can be selective catalytic oxidation of benzyl alcohol to benzaldehyde in the mixture solution of acetonitrile and water, with the conversion rate of 99.6% and 100% selective in 30 minutes. The effects of reaction temperature, the amount of catalyst and the air flow have been comprehensive investigated, and discussed the mechanism of the catalytic reaction.