The following post has been submitted by Max Temple
Atomic hydrogen is critical to maximize hydrogen absorption into nickel. Nickel by itself can disassociate molecular hydrogen (H2) into atomic hydrogen (H1) but the process can be slow and inefficient. However, palladium (Pd) is an element that can rapidly disassociate molecular hydrogen into atomic hydrogen. The process of one catalytic element breaking apart molecular hydrogen (H2) and converting it into atomic hydrogen (H1) so the newly separated atoms can then literally move off the surface to interact with another substance is called, “Hydrogen spillover.”
In the top portion of this diagram, the hypothetical (although the basic phenomenon would be backed up by a huge amount of scientific literature) palladium E-Cat catalyst disassociates molecular hydrogen (H2) into atomic hydrogen (H1) that can then rapidly and efficiently diffuse through the surface of the nickel powder particle and be absorbed into the lattice.
In the lower diagram, a high surface area nickel powder with features often referred to as (cavities, tubules, micro-caves) and other terms by Andrea Rossi is utilized. The palladium catalyst particle which may be much smaller in diameter that the nickel particle enters into one of these surfaces features, being surrounded in all directions.
This results in a more direct path for the disassociated hydrogen to “spillover” onto the nickel for adsorption. Moreover, being trapped in the cavity (imagine possibly the ring of a volcano) there is no where for the atomic hydrogen to go except for into the nickel. Likely, since the H1 produced on the palladium surface does not stick to the palladium surface with the same degree of bonding, some H1 atoms easily and naturally detach from the palladium.
Other H1 atoms that are more strongly bonded may require pulsations or increases of heat and/or pressure to break free. Repeated thermal cycles may maximize the absorption of catalytically split atomic hydrogen into the nickel lattice. After an adequate loading is achieved, producing exotic hydrogen species, stimulation via thermal shocks or EM stimulation may result in excess heat production.
This slideshow includes additional information and referencesnanopd
Adams, Brian D. and Aicheng Chen “The role of palladium in a hydrogen economy”, Materials Today June 2011
Konda, Shuresh K. and Aicheng Chen “Palladium based nanomaterials for enhanced hydrogen spillover and storage” Materials Today March 2016