3D Bimodal Porous Amorphous Carbon with Self-Similar Porosity by Low-Temperature Sequential Chemical Dealloying

Synthesizing 3D porous carbon with atomic-scale control in geometry and topology of porous architectures is of great significance while it technically remains challenging. Dealloying, the selective dissolution of less-stable elemental components from an alloy, is one of the most effective top-down approaches to fabricate 3D nanoporous materials for a wide range of functional applications. Here, we report a sequential metastable-carbide-mediated chemical dealloying approach to fabricate 3D bimodal porous amorphous carbon that possesses geometrically well-defined and topologically self-similar meso- and microporosities. The synthetic route allows independent and precise control of the bimodal porosity, by which micropores can be regulated at angstrom-scale accuracy, and mesopores can be tailored over a wide range of lengths from several nanometers to hundreds of nanometers. The 3D bimodal porous amorphous carbon enables fast ion diffusion and hence delivers outstanding rate performance when used as the anodes for Na-ion storage. This study not only offers a new method for the controllable synthesis of 3D porous carbon materials but also demonstrates the capability of dealloying as an advanced material-processing method to engineer the porous structure down to the angstrom level.