配位还原制备膦酸功能化Pd/C催化剂及其应用

采用活性炭为载体，乙二胺四亚甲基膦酸（EDTMPA）作为配位剂和稳定剂，氯化钯（PdCl₂）为前驱体，硼氢化钠（NaBH₄）为还原剂，通过一步还原制备得到膦酸功能化的超细高分散Pd/C催化剂.透射电子显微镜（TEM）及X射线衍射（XRD）分析结果表明，制得的Pd/C催化剂中Pd粒子的平均粒径为2.7 nm，分散度为37.1%，高于同类型商业化催化剂.制得的催化剂对罗丹明（RhB）和对硝基苯酚（4-NP）的催化加氢反应的活化能分别为27.18和16.79 kJ/mol，明显低于商业化Pd/C催化剂（57.12和55.71 kJ/mol）.

Preparation of Phosphoric Acid-functionalized Pd/C Catalyst by Coordination Reduction and Its Application

We presented a one-step reduction approach to the synthesis of highly dispersed and ultrafine phos-phonate functionalized Pd nanoparticles supported by carbon(Pd/C) using XC-72 as the catalyst support, ethylenediamine tetramethylene phosphonic acid( EDTMPA) as both coordination agent and stabilizer, palla-dium chloride(PdCl2) as the precursor and sodium borohydride(NaBH4) as the reducing agent, respectively. Transmission electron microscopy ( TEM ) and X-ray diffraction ( XRD ) analysis results indicated that the average particle size and the dispersion degree in the Pd/C catalysts are 2. 7 nm and 37. 1％, respectively, much higher than those of the commercial catalysts. The activation energy of catalytic hydrogenation for rhoda-mine(RhB) and p-nitrophenol(4-NP) for the obtained catalyst are calculated to be 27. 1 and 16. 9 kJ/mol, respectively, obviously lower than those in the commercial Pd/C catalyst(57. 2 and 55. 7 kJ/mol).