A sustainable single-component Silk nacre

Synthetic composite materials constructed by hybridizing multiple components are typically unsustainable due to inadequate recyclability and incomplete degradation. In contrast, biological materials like silk and bamboo assemble pure polymeric components into sophisticated multiscale architectures, achieving both excellent performance and full degradability. Learning from these natural examples of bio-based single-componentcomposites will stimulate the development of sustainable materials. Here, we report a single-component Silk nacre, where nacre's typical brick-and-mortar structure has been replicated with silk fibroin only and by a facile procedure combining bidirectional freezing, water vapor annealing, and densification. The biomimetic design endows the Silk nacre with mechanical properties superior to those of homogeneous silk material, as well as to many frequently used polymers. In addition, the Silk nacre shows controllable plasticity and complete biodegradability, representing an alternative substitute to conventional composite materials.

Automated summary

Biological materials such as silk and bamboo assemble pure polymeric components into sophisticated structures, achieving both excellent performance and full degradability. Mimicking these natural examples will stimulate the development of sustainable materials. Silk nacre, with superior mechanical properties and complete biodegradability, represents an alternative to conventional composite materials.