The heterogeneous bifunctional catalyst UiO-66-NH2/Pd with Pd nanoparticles has been prepared on metal-organic framework of UiO-66-NH2 using the impregnation and reduction method .The materials were characterized by X ray diffraction (XRD) ,Fu Liye transform infrared spectroscopy (FT-IR) ,transmission electron microscopy (TEM ) and scanning electron microscopy (SEM) .The resulting material of UiO-66-NH2/Pd was further evaluated as a potential bifunctional heterogeneous catalyst for olefine hydrogenations and Knoevenagel condensation between benzaldehyde and ethyl cyanoacetate .The results showed that the weight percent of Pd in UiO-66-NH2/Pd was 34.% and the average Pd particle size of was about 1 nm .The introduction of Pd nanoparticles did not change the framework integrity of UiO-66-NH2 .The resulting bifunctional catalyst of UiO-66-NH2/Pd was first tested in olefine hydrogenations and the results demonstrated that the material was active and stable as a heterogeneous catalyst .It could be reused for at least 6 times without significant loss of its catalytic performance in styrene hydrogenation .Remarkably ,its structure was stable during the reactions .Furthermore ,it also showed good activity and recycle stability in Knoevenagel condensation between benzaldehyde and ethyl cyanoacetate .%以UiO-66-NH2纳米粒子为载体,采用浸渍和还原的方法制备了担载Pd纳米粒子的多相双功能催化剂UiO-66-NH2/Pd.用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、透射电镜(TEM)、扫描电镜(SEM)等手段对材料进行了表征,并分别以芳香烯烃的催化加氢、苯甲醛和氰基乙酸乙酯的Knoevenagel缩合反应为模型反应,考察了UiO-66-NH2/Pd材料的加氢和碱催化性能.研究结果表明,通过浸渍和还原的方法在UiO-66-NH2上引入了粒径为1 nm左右的Pd纳米粒子,Pd的质量分数为3.4%,材料的结构未发生明显变化.催化剂UiO-66-NH2/Pd能够高效催化多种烯烃的加氢反应,在苯乙烯的催化加氢反应中,催化剂循环使用6次,转化率大于96%,催化剂结构没有明显变化,催化剂U iO-66-NH2/Pd依然具备很好的碱催化能力,在苯甲醛和氰基乙酸乙酯的Knoevenagel缩合反应中表现出较好的催化活性和循环稳定性.
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