Bio-inspired three-dimensional carbon network with enhanced mass-transfer ability for supercapacitors

Abstract Governing mass-transfer process, the interface of electrode/electrolyte greatly affects the performance of electrochemical energy storage applications. Inspired by the spider web, a 3D carbon network (3DCN) with bionic surface is fabricated by using the zeolitic imidazolate frameworks (ZIF) as the precursors. In this strategy, 3D carbon network serves as the matrix for the formation of ZIF-8 nanoparticles. A following calcination enables these nanoparticles fuse into continuous network and introduce “spindle-knot” structure on the surface of carbon matrix. The further examines reveal that this specially designed nanostructure enables the liquid to transfer in a fast way. Powered by the "spider web" pattern, the obtained material (S-3DCN) shows great potential in the electrolyte-based applications. As the electrode in supercapacitor, S-3DCN shows a specific capacitance of 395 F g −1 at the current density of 1 A g −1 and delivers energy much faster than other similar carbon materials. Assembled in a solid-state supercapacitor device, S-3DCN achieves the high energy density for practical applications.