Hierarchical Amorphous–Crystalline Ceramic Nanotube Array Nanocomposites with Superior Mechanical and Functional Properties

Despite extensive efforts to develop high-performance ceramic nanocomposites, specially achieving both high stiffness and high damping remains challenging because these properties are typically mutually exclusive. Here, a bottom-up strategy is developed to fabricate an enamel-inspired ceramic nanotube array nanocomposite by assembling highly ordered amorphous/crystalline-titania nanotube arrays infiltrated with a polymethyl methacrylate matrix on a large scale. This nanocomposite simultaneously exhibits high stiffness (nanoindent Young's modulus: ≈71.4 GPa; nanoindent hardness: ≈4.3 GPa), high damping (tanδ: ≈0.07), exceptional energy dissipation (≈4.6 µJ µm^-3), and excellent fatigue resistance that surpass those of conventional and biomimetic ceramic-based materials, while also offering good processability (can be sculptured into various shapes), biocompatibility (no tissue damage or abnormal immune responses in vivo), and corrosion resistance. The remarkable mechanical performance arises from the robust amorphous/crystalline ceramic nanotube array skeleton and the abundant three-phase interfacial adhesion. This work expands the hierarchical dimensionality of enamel-like material design by precisely tailoring the heterogeneous phases within nanotubes, positioning this nanocomposite as a promising candidate for multipurpose applications that demand exceptional dynamic load-bearing capacity, exemplified by the electronic substrate of a dental patch for oral health monitoring.