2025/05/07 by Bapari, Sambit, Weissmüller, Jörg
#Dealloying | Metal hydrides | Miscibility gap | Nanoporous | Palladium alloys #Natural Sciences and Mathematics::541: Physical #Technology::620: Engineering::620.1: Engineering Mechanics and Materials Science #Theoretical
paper · doi:10.15480/882.15135
Metal hydrides that enable reversible solute exchange with a reservoir often exhibit a miscibility gap at room temperature. Misfit strain during two-phase coexistence may then lead to degradation on repeated charging/discharging cycles. Furthermore, the miscibility gap impairs continuous and uniform composition tuning for functional applications. We explore electrochemical dealloying as a pathway to macroscopic monolithic samples of nanoporous Pd–Pt with continuous solubility for H at room temperature. The ligament size is tunable in the range of 4–40 nm, and sorption isotherms suggest a miscibility-gap critical point marginally below room temperature. With a maximum hydrogen fraction of 0.5, we demonstrate a reversible actuation strain of 3.3 % and a high cycle stability.