Composition-Tuned Pt-Skinned PtNi Bimetallic Clusters as Highly Efficient Methanol Dehydrogenation Catalysts

Abstract

Platinum is the most active anode and cathode catalyst in next-generation fuel cells using methanol as liquid source of hydrogen. Its catalytic activity can be significantly improved by alloying with 3d metals, although a precise tuning of its surface architecture is still required. Herein, we report the design of a highly active low temperature (below 0 • C) methanol dehydrogenation anode catalyst with reduced CO poisoning, based on ultra-low amount of precisely-defined PtxNi1-x (x = 0 to 1) bimetallic clusters (BCs) deposited on inert flat oxides by Cluster Beam Deposition (CBD). These BCs feature clear composition-dependent atomic arrangements and electronic structures stemming from their nucleation mechanism that are responsible for a volcano-type activity trend peaking at the Pt0.7Ni0.3 composition. Our calculations reveal that at this composition a cluster skin of Pt atoms with d-band centres downshifted by subsurface Ni atoms weakens the CO interaction that in turn triggers a significant increase in the methanol dehydrogenation activity.

Multidimensional thermally-induced transformation of nest-structured complex Au-Fe nanoalloys towards equilibrium

“…While onion-ring structures were reported as the putative global minima of several nanoalloys [93], kinetics is generally found to play an essential role in their formation [94]. In agreement with our results, the onion-shell formation was also found for Ag-Au [95], Ni-Pt [96], and Mo-Cu [97] NPs as a result of kinetic trapping and the interplay between the (fast) coalescence of the core and the (slower) diffusion of elements within the NP. The present simulations additionally show an influence of temperature on the Au and Fe radial densities (Fig.…”

Stabilized open metal sites in bimetallic metal–organic framework catalysts for hydrogen production from alcohols

“…Current research efforts focus on developing efficient carriers and advanced catalysts to increase reaction rates and provide a more stable hydrogen generation and storage process. To achieve a high hydrogen capacity, researchers have investigated a number of promising LOHCs, including several alcoholbased molecules: methanol (12.1 wt% H 2 ), [13][14][15] ethylene glycol (6.5 wt% H 2 ), 16 and other alcohols. 17 Although methanol is a high capacity hydrogen carrier, it requires the separation of CO to produce high purity hydrogen gas, making it less attractive for use with fuel cells where even minor CO contamination can lead to catalyst poisoning.…”

Light‐Driven Alcohol Splitting by Heterogeneous Photocatalysis: Recent Advances, Mechanism and Prospects

“…For example, structures and properties of the co‐catalysts determine both the hydrogen evolution reaction and the possible side‐reactions. It has been well‐known that different kinds of metals can form solid solutions, [115,134,152] intermetallic compounds, [127,133,134,153,154] and versatile nanostructures (e. g. core‐shell structures) [31,134,155] . Investigating structures of the co‐catalysts as well as the metal/semiconductor interfaces on the atomic level utilizing spherical‐aberration‐corrected TEM and scanning TEM (STEM) will certainly create more exciting results.…”