DFT study on interaction of hydrogen with Pd(111)

Grain-growth mediated hydrogen sorption kinetics and compensation effect in single Pd nanoparticles

Grains constitute the building blocks of polycrystalline materials and their boundaries determine bulk physical properties like electrical conductivity, diffusivity and ductility. However, the structure and evolution of grains in nanostructured materials and the role of grain boundaries in reaction or phase transformation kinetics are poorly understood, despite likely importance in catalysis, batteries and hydrogen energy technology applications. Here we report an investigation of the kinetics of (de)hydriding phase transformations in individual Pd nanoparticles. We find dramatic evolution of single particle grain morphology upon cyclic exposure to hydrogen, which we identify as the reason for the observed rapidly slowing sorption kinetics, and as the origin of the observed kinetic compensation effect. These results shed light on the impact of grain growth on kinetic processes occurring inside nanoparticles, and provide mechanistic insight in the observed kinetic compensation effect.

Grains are the building blocks of crystalline solids. Here the authors show how hydrogen-sorption induced grain-growth in Pd nanoparticles slows down the hydrogen sorption kinetics and constitutes the physical origin of corresponding kinetic compensation.

How the hydrogen sorption properties of palladium are modified through interaction with iridium

The instability of hydrogen sorption properties in Ir (positive sorption energies) leads to the destabilization of hydrogen sorption in a Pd layer interacting with Ir.

Performance of facet-controlled Pd nanocrystals in 2-ethylanthraquinone hydrogenation

The Pd (100) facet is more active than Pd (111) in CO hydrogenation but less active in saturation of aromatic rings.