General synthesis of ultrahigh-surface-area porous carbons with superior yield via preferential removal of sp2-hybridized atoms

A grand challenge in the state-of-the-art porous carbons is the lack of reliable synthesis strategy for achieving ultrahigh surface areas while maintaining a high carbonization yield. Generally, the realization of the ultrahigh surface area depends on the inherent properties of the starting precursors. Meanwhile, excessive development of porosity (>3500 m(2) g(-1)) will undoubtedly give rise to low carbonization yield (<10%), thus far restricting cost-effective applications. Here, we report a general protocol via constructing nitrogen-doped sp(2)-hybridized carbon atoms in the carbonaceous matter, which guides the pore-creating agents (e.g., KOH) to preferentially etch over sp(2)-rather than sp(3)-hybridized atoms, thus greatly increasing the activation reaction efficiency to simultaneously accomplish ultrahigh porosity without sacrificing carbonization yield, a critical paradox in producing carbons. A highest Brunauer-Emmett-Teller surface area (i.e., 4376 m(2) g(-1)) with 10 wt% carbonization yield and 3829 m(2) g(-1) with an unparalleled yield of 35.1 wt% are achieved so far, which enables great potential in adsorptive-related applications as exemplified by their record-high gas adsorption and supercapacitve performances. Our findings reveal important insights on directed synthesis of ultrahigh-surface-area carbons and provide an impetus for their on-demand applications. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study demonstrates a successful approach to achieve ultrahigh surface areas and high carbonization yields in carbonaceous materials by constructing nitrogen-doped sp(2)-hybridized carbon atoms to guide pore-creating agents. This provides important insights for the directed synthesis of high-surface-area carbons and their potential applications.