Zhang Fengwei, Liu Mengmeng, Liu Qiang, Li Jingjing, Li Boyang, Dong Zhengping
Institute of Crystalline Materials, Institute of Molecular Science, Shanxi University, Taiyuan, 030006, P. R. China.
College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China.
Chem Asian J. 2021 Oct 4;16(19):2952-2957. doi: 10.1002/asia.202100740. Epub 2021 Aug 19.
In-situ encapsulation of tiny and well-dispersed Pd nanoparticles (Pd NPs) in zeolitic imidazolate frameworks (ZIFs) was firstly achieved using a one-pot and facile methanol-mediated growth approach, in which methanol served as both solvent and a mild reductant. The microstructure, morphology, crystallinity, porosity as well as evolution process of the catalysts were determined by TEM, XRD, N adsorption and UV-vis spectra. Due to the complete encapsulation of such Pd NPs combined with ultrahigh surface area and uniform microporous structure of ZIF-8, the resulting Pd@ZIF-8-60 min nanocomposite exhibited more superior catalytic activity for olefins hydrogenation with TOF of 7436 h and excellent size selectivity than previously reported catalysts. Furthermore, the catalyst displays excellent recyclability for 1-octene hydrogenation and without any loss of the Pd active species.
首先采用一锅法且简便的甲醇介导生长方法，在沸石咪唑酯骨架（ZIFs）中原位封装微小且分散良好的钯纳米颗粒（Pd NPs），其中甲醇既作为溶剂又作为温和的还原剂。通过透射电子显微镜（TEM）、X射线衍射（XRD）、氮吸附和紫外可见光谱确定了催化剂的微观结构、形态、结晶度、孔隙率以及演变过程。由于此类Pd NPs的完全封装，结合ZIF-8的超高表面积和均匀的微孔结构，所得的Pd@ZIF-8-60分钟纳米复合材料对烯烃氢化表现出更优异的催化活性，其转化频率（TOF）为7436 h，并且尺寸选择性优于先前报道的催化剂。此外，该催化剂对1-辛烯氢化显示出优异的可回收性，且钯活性物种没有任何损失。
