Tunable Architectures of Ag-Modified Nanoporous Cu Foils via Sequence-Controlled Ga-Assisted Alloying/Dealloying for Bifunctional Catalysis

Self-supported nanoporous metal foils with precisely engineered architectures are promising for catalysis, sensing, and environmental remediation, yet their scalable fabrication remains challenging. Here, we present a sequence-controlled liquid gallium (Ga)-assisted alloying/dealloying strategy, integrated with thermal evaporation, to construct Ag-modified nanoporous copper (Cu) foils. By varying the Ag deposition sequence, two distinct architectures were obtained: one features Ag 3 Ga intermetallic decorations, while the other forms a continuous Ag network within the nanoporous Cu. Subsequent electrooxidation generates Cu x O nanoneedles as catalytically active sites. The architecture with dispersed Ag 3 Ga yields exceptional non-enzymatic glucose sensing with high sensitivity, low detection limit, and long-term stability. In contrast, the continuous Ag network promotes outstanding photo‑Fenton degradation of organic dyes within minutes and excellent reusability. This work demonstrates a versatile approach to spatially control noble metal distribution in nanoporous Cu foils, enabling multifunctional catalytic systems for biosensing and environmental purification.