Preparation and characterization of Pt nanoparticles supported on a Fe‐doped hydroxyapatite‐activated Vulcan XC72 composite material

Abstract

Summary In this research, the hydroxyapatite (HAp) could be directly deposited on carbon black (CB), which was the modified surface to generate more OH− free radicals to strengthen the bond between HAp and CB, before adding ((NH4)2Fe(SO4)2·6H2O) to engage the ion exchange with Fe2+ and Ca2+ to obtain FeHAp‐CB composites. The Pt nanoparticles were then reduced on the FeHAp‐CB composite surface to derive a Pt/FeHAp‐CB catalyst of dual function. The catalyst revealed a steep desorption peak at −0.180 V (vs Ag/AgCl) in a hydrogen oxidation reaction ascribed to the characteristics of Pt (110) facet and the CO detoxication function in the methanol oxidation reaction. The superior performance of Pt/FeHAp‐CB/CB catalyst was apparently related to the Pt (110) surface, the Fe concentration, and the homogeneous dispersion of Pt particles on the FeHAp‐CB composites. And, the ratio of coexisting Pt0 and Pt2+ within Pt/FeHAp‐CB/CB catalyst would definitely affect chemical stability and mass activity. By X‐ray photoelectron spectroscopy (XPS), it was found that a high quantity of Pt0 could improve mass activity, while a high quantity of Pt2+ contributed to chemical stability.

Phosphotungstic acid‐Titania loaded polyaniline nanocomposite as efficient methanol electro‐oxidation catalyst in fuel cells

“…The efficiency of the overall methanol oxidation reaction (MOR) depends on the anode catalyst in DMFC. 4 In DMFC, mostly platinum-based catalysts are used in methanol oxidation, but this system has the utmost crucial disadvantages, including the reaction getting poisoned by the adsorbed carbon monoxide (CO) formed on its surface 5,6 and also high cost, lower reliability, and durability. 7 As an alternate, the above drawbacks can be overcome by the nanomaterial-based electrocatalyst, which plays a vital role in fuel cell application due to its higher surface area and enhances the rate of an electrochemical reaction.…”