采用溶剂热法合成了Pt/Fe3O4@C磁响应核壳催化剂,以扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)和超导量子干涉磁强计(SQUID)对催化剂的结构和磁性质进行了表征。研究发现Pt颗粒均匀地分散在碳层上,Pt/Fe3O4@C催化剂显示了良好的超顺磁性。研究了Pt/Fe3O4@C磁响应催化剂上肉桂醛(CAL)的选择性加氢反应,结果显示催化剂具有良好的C=O加氢活性,在考察的条件下,肉桂醛转化率在60%左右时,肉桂醇选择性可达96%以上。催化剂在外加磁场作用下可以高效地从液相反应体系中分离,经多次循环使用后仍具有良好的催化性能。
Magnetically responsive core-shell structured Pt/Fe3O4@C catalysts were synthesized by a solvothermal method. Various techniques such as scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), and superconducting quantum interference device(SQUID) were used to characterize the structure and magnetic properties of the prepared Pt/Fe3O4@C catalysts. The results reveal that Pt particles are uniformly dispersed on the carbon shell. Additionally, the magnetic measurements show that the magnetically responsive Pt/Fe3O4@C catalysts display excellent superparamagnetic properties at room temperature. Selective hydrogenation of cinnamaldehyde on the catalysts was carried out in a high-pressure batch reactor, showing a superior activity in the hydrogenation of the C=O bond and a selectivity of 96 % to cinnamyl alcohol with a cinnamaldehyde conversion of about 60 %. Additionally, the catalysts can be efficiently recovered from the reaction medium under the external magnetic field and maintain its catalytic properties after used for several recycles.