Liquid metal dealloying enables low-temperature synthesis of nanoporous β-SiC with an interconnected nanoplate network

Developing an external-template-free route for synthesizing nanoporous covalent ceramics remains challenging because their strong covalent bonding typically necessitates high-temperature processing, which can limit nanoscale architectural control. Here, we report the fabrication of three-dimensional nanoscale bicontinuous porous β-SiC (3Dnbp-β-SiC) at 1073 K through a top-down metallurgical route based on liquid metal dealloying. During this process, a Mn 5 SiC precursor with a layered crystal structure was immersed in molten Bi, where Mn was selectively dissolved while the residual Si–C framework self-organized into crystalline β-SiC. Unlike the nearly isotropic ligament networks commonly observed in conventional dealloying systems, the product comprises a bicontinuous porous architecture constructed from interconnected nanoplates and exhibits a mesoporous structure with a BET surface area of 56.9 m 2 g −1 . These results highlight liquid metal dealloying as a viable metallurgical strategy for fabricating nanoporous covalent ceramics at a relatively low temperature.