Ultrafast volumetric assembly of layered nanocomposites at dynamic gelation interface

Abstract

Biomimetic learning has boosted the development of layered nanocomposites with superior mechanical properties, fast ion conduction, high barrier capacities, and high conductivities, resulting in numerous practical applications in artificial structural materials, energy storage, filtration, and electromagnetic shielding. These outstanding properties arise from the highly oriented layered structure. Convenient fabrication and complex shapes are required for practical applications. However, conventional strategies, including ice templating, vacuum filtration, and electromagnetic induction, are constrained by time-consuming fabrication and sample shapes, restricting their extension to large-scale applications. Here, we present a facile, universal, and scalable strategy for fabricating layered nanocomposites using ion diffusion-induced directional gelation. This ultrafast volumetric production, including controllable thickness growth with no size restriction, results from continuous gelation and convenient post-processing, whose fabrication rate is 21.7 times that of ice templating, 13.2 times that of vacuum filtration, and 3.1 times that of electromagnetic induction. Furthermore, layered alumina/epoxy nanocomposites were prepared with superior specific strength (2.9 MPa m1/2/(Kg/m3)) and specific toughness (96.2 MPa/(Kg/m3)), demonstrating the validity of our strategy for layered structures. Moreover, our approach can be extended to other material systems and arbitrary shapes for multifunctional applications in wearable devices, sensors, and anti-corrosion coatings.