配位还原制备膦酸功能化Pd/C催化剂及其应用

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

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(PdCl_2)为前驱体,硼氢化钠(NaBH_4)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).

We presented a one-step reduction approach to the synthesis of highly dispersed and ultrafine phosphonate 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,palladium chloride（ PdCl_2） as the precursor and sodium borohydride（ NaBH_4） 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 rhodamine（ 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）.