Facile synthesis of hollow spherical sandwich PtPd/C catalyst by electrostatic self-assembly in polyol solution for methanol electrooxidation

• Published in: Journal of power sources Vol. 203; pp. 17 - 25
• Main Authors: Chu, Yuan-Yuan, Wang, Zhen-Bo, Jiang, Zheng-Zhi, Gu, Da-Ming, Yin, Ge-Ping
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.04.2012; Elsevier
• Subjects: Anodizing; Applied sciences; Catalysis; Catalysts; Catalysts: preparations and properties; Chemistry; Direct energy conversion and energy accumulation; Direct methanol fuel cell; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrochemistry; Electrostatic self-assembly; Electrostatics; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; General and physical chemistry; Hollow spherical PtPd/C catalyst; Methanol electrooxidation; Methyl alcohol; Microwave-assisted ethylene glycol process; Miscellaneous (electroosmosis, electrophoresis, electrochromism, electrocrystallization, ...); Palladium; Scanning electron microscopy; Self assembly; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Microwave-assisted ethylene glycol process; Hollow spherical PtPd/C catalyst; Direct methanol fuel cell; Methanol electrooxidation; Electrostatic self-assembly; Performance evaluation; Self assembly; Carbon dioxide; Solid solution; Porous material; Supported catalyst; Electrocatalysis; Platinum; Sodium sulfate; Oxidation; Polyol; Methanol; Ethylene glycol; Scanning electron microscopy; Sandwich structure; Alcohol fuel cells; X ray diffraction; Energy dispersion; Morphology; Poisoning; Porosity; Comparative study
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2011.11.025

PtPd/C catalyst with hollow spherical sandwich structure was successfully prepared by electrostatic self-assembly one-step reductive route using sodium dodecyl sulfate as the capping and structure-directing agent in ethylene glycol solution by microwave-assisted process. It can prevent Pd metal from oxidation and dissolution, and enhance its stability and activity toward methanol electrooxidation. [Display omitted] ► The hollow spherical sandwich structure with open porosity and integrity was successfully synthesized by electrostatic self-assembly route. ► The high activity and stability of hollow spherical PtPd/C catalyst for methanol electrooxidation were obtained. ► The new mechanism of methanol oxidation on the hollow spherical PtPd/C catalyst was proposed. A novel PtPd/C catalyst with hollow spherical structure has been successfully prepared by electrostatic self-assembly one-step reductive route using sodium dodecyl sulfate as a capping and structure-directing agent in ethylene glycol solution by microwave-assisted process. The structure, composition, and morphology of as-prepared catalyst are characterized by X-ray diffraction, energy dispersive analysis of X-ray, scanning electron microscope, and transmission electron micrograph, respectively. The as-prepared PtPd/C catalyst has a novel hollow spherical sandwich structure with open porosity and integrity, which can prevent Pd metal from oxidation and dissolution, and enhance electrocatalytic activity and stability toward methanol electrooxidation in comparison with the solid solution PtPd/C alloy and Pt/C catalysts. The results of electrochemical measurement demonstrate the enhancement of the CO-tolerant ability of hollow spherical PtPd/C catalyst by the new insight into the mechanism that Pd can efficiently directly oxidize the poisoning intermediates from methanol electrooxidation, such as HCOOH, to CO 2, which promotes its catalytic efficiency and results in much higher electrocatalytic activity than Pt/C on a mass basis. Therefore, the effective and facile method to prepare PtPd/C catalyst with hollow spherical sandwich and porous structure and better catalytic performance is very important and desirable in direct methanol fuel cell applications.