Hydrogen Evolution and Hydrogen Oxidation on Palladium Bismuth Alloys

Abstract

Thin film alloys of PdBi have been synthesised using a high throughput physical vapour deposition method to produce compositional gradients of PdBi alloys. XPS indicates that for the non-equilibrated thin films, the surface composition is the same as the bulk, and core level shifts reflect the inter-metallic interaction between the component metals. Hydrogen absorption is hindered in the PdBi alloys, and at a composition of 70 at.% bismuth, the aBi 2 Pd bulk alloy phase is identified in XRD. This phase exhibits a maximum in the hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR) electrocatalytic activity. The increased activity of the alloy can be understood in terms of the Pd d-band density of states, and a concomitant increase in the binding energy of hydrogen. There is a strong correlation between the HER and HOR activity as a function of composition across the complete range of alloys. The potential of using the aBi 2 Pd bulk inter-metallic phase at the anode of PEM fuel cells is briefly discussed.

Reduced graphene oxide nanosheets decorated with Au, Pd and Au–Pd bimetallic nanoparticles as highly efficient catalysts for electrochemical hydrogen generation

“…Thus, modification of the surface properties coupled with metal alloying are necessary to improve the electrocatalytic properties of Pd NPs. [10][11][12][13] In this context, attention may be shifted towards the use of alloyed NPs of Pd with other support that could bring changes in the electronic and geometrical properties of pure Pd. 11,14 For instance, bimetallic NPs comprising two different metal elements in the form of core-shell, alloy or heterostructures displayed enhanced chemical and physical properties and exhibited high catalytic/electrocatalytic properties.…”

“…17 Likewise, alloying Pd with other noble and transition metals, active electrocatalysts 4 for HER were synthesized. 12,14,18,19 Amongst bimetallic alloy systems, Au-Pd alloy is an ideal candidate for HER. 18,19 With the idea of improving the electrocatalytic activity of the electrocatalyst, loading the nanostructures on various carbon supports such as carbon nanotubes, carbon black or graphene has been suggested.…”

Electrochemical Dealloying of PdCu3 Nanoparticles to Achieve Pt‐like Activity for the Hydrogen Evolution Reaction

“…[2a] Therefore, development of non-Pt-basedc atalystst hat are superioro rc omparablet oP ti ss till desperately neededf or the successful application of water splittingf or hydrogen generation. [16] On the other hand, in comparison witho ther inexpensive metals (e.g.,N i, Co, and Mo), Cu is low cost and highly abundant.R ecently,C u-based catalysts have shownc onsiderable activities towards HER both in acidic/basic and neutral medium. [14] Though Pd is highly active for hydrogen evolution, it enhances the hydrogen solubility under appropriate temperature and pressure, which leads to the formationo fh ydride phases and lattice expansion causing instability.…”

“…[15] Formation of hydride can be suppressed to al arge extent by alloyingo fP dw ith other metals. [16] On the other hand, in comparison witho ther inexpensive metals (e.g.,N i, Co, and Mo), Cu is low cost and highly abundant.R ecently,C u-based catalysts have shownc onsiderable activities towards HER both in acidic/basic and neutral medium. [3c, 7, 17] In the presents tudy,w er eport an ew catalyst derived from electrochemical dealloying of PdCu 3 intermetallic NPs for highly efficient electrochemical HER.…”

High‐throughput methods using composition and structure spread libraries

“…In the previous example, the activity of Pd was promoted by alloying with a more inert metal. Consequently, an investigation of PdBi alloys was undertaken using a composition gradient sample with an array of electrodes as previously described . Promotion effects were also observed, although they were not as strong as those observed in the PdAu work, and they were attributed to the formation of an α Bi Pd intermetallic phase.…”