碳笼负载镍基磁性催化剂Ni@Cage-C的制备与性能研究

Preparation and Properties of Carbon Cage Supported Nickel-Based Magnetic Catalyst Ni@Cage-C

以自然结晶法制备的ZIF-67为前驱体,采用包裹-刻蚀-碳化策略,得到大小均匀的纳米碳笼(Cage-C),再于液相条件下以碳笼为载体负载上活性金属镍(Ni),成功制备了非贵金属磁性催化剂Ni@Cage-C,并应用于对硝基苯酚催化还原反应以考察其多相催化性能。结果表明:优化条件下制备的Ni@Cage-C催化剂为碳笼包裹单质镍结构,其平均颗粒大小为550 nm;将Ni@Cage-C用于对硝基苯酚催化还原反应时,催化性能明显优于参照催化剂雷尼镍(Raney-Ni)。质量反应速率常数kM为6.11 mg^(-1)·min^(-1),催化效率达到98.87%,循环反应十圈后活性仍高于初始活性的85%。

In this paper,a non-noble metal magnetic catalyst Ni@Cage-C was successfully prepared.By using ZIF-67 as the precursor,carbon cage(Cage-C)nanoparticles with uniform size were obtained by means of encapsulation-etching-carbonization strategy.Then the active metal nickel was supported by Cage-C in liquid phase.The catalytic reduction of p-nitrophenol to p-aminophenol was employed to evaluate the catalytic performance of Ni@Cage-C.The results indicated that the Ni@Cage-C catalyst prepared under optimized conditions had a carbon cage coated nickel structure with an average particle size of about 550 nm.When it was used for the reduction of p-nitrophenol,its comprehensive catalytic performance was obviously better than the reference catalyst(Raney-Ni),with the mass reaction rate constant kM of 6.11 mg^(-1)·min^(-1),the catalytic effi ciency of 98.87%,and the catalytic conversion rate maintaining more than 85%after 10 cycles of the catalytic reaction.