Preparation and characterization of platinum/iron contained hydroxyapatite/carbon black composites

摘要

In this report, calcium ions in the porous hydroxyapatite (HAp) microspheres are partially exchanged with ferrous ions to form iron contained hydroxyapatite (FeHAp) on which Pt ions in H_2PtCl_6 solution are reduced to form Pt/FeHAp catalyst and finally mixed with carbon blacks to derive Pt/FeHAp/C catalysts. They exhibit the characteristics of Pt (110) facet with a sharp desorption peak at -0.109 V (vs. Ag/AgCl), the electrochemical surface area (ECSA) ranging from 73 to 224 m~2 g~1 with little CO poisoning effect on Pt, and the mass activity ranging from 6.88 to 28.99 A gpt~1 in methanol oxidation reaction (MOR) at 0.4 V (vs. Ag/AgCl). Besides, Pt/FeHAp reveals the lower onset potential in CO-stripping than Pt/C. These better performances of Pt/FeHAp/C catalysts, compared with Pt/C, are also related to the Pt (110) facet, the content of Fe, and the coexistence of Pt~0 and Pt~2 in Pt/FeHAp.