I do not know what materials they are using.
I would suggest you ask Fleischmann, but he is dead. I spent a week with him discussing these matters, and I read everything he wrote, so I know what he thought and where he got his numbers. If you want to claim you know more about palladium and energy than Martin Fleischmann, be my guest. Go ahead and say that. Show the world that you have a swelled head and you think you know better than the Leading Experts.
Of course I can see the advantages of Ni, Ti and other materials. Au might actually be a candidate. Wouldn't that be something? Fort Knox could supply all the energy in the solar system and more, for billions of years.
A sandwich combination of Pd and Ni might be promising.
Pd Ni sandwich. That sounds like what CETI was using. Layers of Pd and NI. Notice also that Swartz also uses a mixture with Ni and Pd. White gold Pd with Au might be interesting as well as Ti with Sn/V.