Hydrogen Permeation Mechanism in Pd-Based Membranes

Hydrogen permeation through Pd-based membranes is based on the dissolution of H2 in metal Pd to form a Pd-H alloy and the diffusion of the H atoms across the membrane, which is described by the solution/diffusion 

Hydrogen diffusion from the bulk gas to the membrane surface. 

Migration of atomic H on the membrane surface into the membrane bulk (dissolution). 

Transition of atomic H from the bulk metal to the membrane surface on the permeate side. 

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