Abstract
Highly active and durable electrocatalysts are vital for commercialization of direct methanol fuel cells. In this work, a three-dimensional nanocomposite consisting of platinum nanoparticles, W18O49 nanocables, and reduced graphene oxide composite (Pt/W18O49 NCs–rGO) has been prepared as an electrocatalyst for methanol oxidation reaction (MOR). The catalyst is prepared through a two-step method. The W18O49 nanocables and the reduced graphene oxide composite are prepared by a solvothermal process. Then, Pt nanoparticles are loaded on the W18O49 nanocables and the reduced graphene oxide composite by a hydrogen reduction at ambient condition. The obtained catalyst has a special three-dimensional architecture consisting of two-dimensional nanosheets, assembled one-dimensional nanocables, and the loaded nanoparticles on their surface. The Pt/W18O49 NCs–rGO catalyst shows 1.56 time mass activities than the Pt/C, with the current density of the forward anodic peak reaching 1624 mA/mgPt at 0.854 V versus reversible hydrogen electrode potential in 0.1 M HClO4 and 0.5 M CH3OH mixed electrolyte. It also shows a strong antipoisoning property toward CO. For the durability testing, the current density of Pt/W18O49 NCs–rGO shows a 37% decay, whereas the current of Pt/C catalyst shows a 41% degradation from 600 to 3600 s at 0.7 V. The high activity toward MOR, good antipoisoning for intermediate products, and excellent stability are ascribed to strong metal–support interaction effects between the Pt nanoparticles and the W18O49 NCs.
Highlights
Platinum-based catalysts were used in both electrodes of direct methanol fuel cells (DMFCs)
Platinum nanoparticles were loaded onto the tungsten oxide to prepare a structural and functional optimization catalyst for methanol oxidation reaction
Morphology and microstructure of the sample were studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively
Summary
Platinum-based catalysts were used in both electrodes of direct methanol fuel cells (DMFCs). Preparing platinum nanoscale catalysts with special morphologies, such as platinum nanoparticles,[1−4] platinum nanonetwork,[5] and other designed Pt nanostructures,[6−10] enable to improve the activity of platinum. It will lose active sites during working, which results from poisoning of intermediate species during anode reaction process in DMFCs.[11−14] To overcome this problem, various metal elements, such as Pd, Ni, and others were used for incorporation into platinum to prepare alloy catalysts.[15−17] It reduces the amount of platinum and improves the ability of CO tolerance via a bifunctional mechanism.[18−20]. The present work provides a promise catalyst for methanol electrocatalytic oxidation and presents an approach for designing various multifunctional materials
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
