Amino-Directed CuPd Dispersion in MOF Coatings for Enhanced Hydrogen Trapping and Embrittlement Resistance

Hydrogen embrittlement (HE) remains a critical challenge in structural metals due to hydrogen ingress and accumulation within the lattice. Herein, we report a metal–organic framework (MOF)-based coating strategy to mitigate HE by incorporating CuPd nanoparticles into amino-functionalized UiO-66-NH2. The amino groups direct the spatial distribution of CuPd within the MOF pores, generating catalytic sites that facilitate hydrogen dissociation and subsequent confinement via the hydrogen spillover effect. Comprehensive characterization using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and small-angle X-ray scattering (SAXS) confirms the structural integrity of the hybrid and the localization of hydrogen near CuPd sites. Slow strain rate tensile (SSRT) tests reveal that UiO-66-NH2–CuPd coatings reduce HE susceptibility from 34.4 to 10.4% and enhance ductility by 42.5% relative to uncoated substrates. These results demonstrate that the synergistic integration of MOF porosity and bimetallic functionality enables efficient hydrogen trapping, suppressing lattice penetration. This work introduces a scalable, nanostructured interface for hydrogen management, offering a new paradigm in HE-resistant materials through controlled pore engineering and spillover enhancement.