Bioinspired large-scale aligned porous materials assembled with dual temperature gradients

• DOI: 10.1126/sciadv.1500849
• Publication Date: 2015-12-12T04:00:32Z
• Authors: Hao Bai; Yuan Chen; Benjamin Delattre; Antoni P. Tomsia; Robert O. Ritchie
• Keywords: Polydimethylsiloxane

Natural materials, such as bone, teeth, shells, and wood, exhibit outstanding properties despite being porous made of weak constituents. Frequently, they represent a source inspiration to design strong, tough, lightweight materials. Although many techniques have been introduced create structures, long-range order the porosity well precise control final architecture remain difficult achieve. These limitations severely hinder scale-up fabrication layered structures aimed for larger applications. We report on bidirectional freezing technique successfully assemble ceramic particles into scaffolds with large-scale aligned, lamellar, porous, nacre-like structure at centimeter scale. This is achieved by modifying cold finger polydimethylsiloxane (PDMS) wedge nucleation growth ice crystals under dual temperature gradients. Our approach could provide an effective way manufacturing novel bioinspired structural in particular advanced materials composites, where higher level over required.