Skeletal High‐Strength Nanoporous Copper and Metamaterials: The Hakka Tulou Design Heritage

Abstract

Abstract Nanoporous metals (NPMs) are pivotal for next‐generation technologies, yet their inherent mechanical fragility has long hindered practical implementation. Drawing inspiration from the ingenious architecture of the ancient Hakka Tulou walls, a novel class of nanoporous copper (NPCu) materials—skeletal NPCu—is developed to overcome this limitation. To achieve this, we leverage the principles of solidification and dealloying in alloy design to engineer a unique two‐phase precursor alloy microstructure. This microstructure comprises a strong, ductile, non‐dealloyable skeletal phase (minor phase) and a readily dealloyable principal phase. Upon dealloying, the precursor transforms into skeletal NPCu, achieving exceptional yield strength (200.4 ± 15.2 MPa)—significantly surpassing that of conventional NPMs. Extending this design concept, we fabricate skeletal NPCu lattice metamaterials that surpass the Gibson‐Ashby strength model predictions by 800%, while offering an outstanding specific surface area (27.6 ± 1.2 m 2  g −1 ) that enhances multifunctionality. By marrying ancient architectural wisdom with modern materials science, this innovation unlocks the vast potential of advanced NPMs for applications spanning energy, aerospace, and beyond.