When high-temperature cesium chemistry meets self-templating. Metal acetates as building blocks of unusual highly porous carbons

Self-templating is a facile strategy for synthesizing porous carbons by direct pyrolysis of organic metal salts. However, the method typically suffers from low yields (<4%) and limited specific surface areas (SSA<2000 m${}^2$ g${}^{-1}$) originating from low activity of metal cations (e.g., K${}^{+}$ or Na${}^{+}$) in promoting construction and activation of carbon frameworks. Here we use cesium acetate as the only precursor of oxo-carbons with large SSA of the order of 3000 m${}^2$ g${}^{-1}$, pore volume approaching 2 cm${}^3$ g${}^{-1}$, tunable oxygen contents, and yields of up to 15 %. We unravel the role of Cs${}^{+}$ as an efficient promoter of framework formation, templating and etching agent, while acetates act as carbon/oxygen sources of carbonaceous frameworks. The oxo-carbons show record-high CO${}_2$ uptake of 8.71 mmol g${}^{-1}$ and an ultimate specific capacitance of 313 F g${}^{-1}$ in the supercapacitor. This study helps to understand and rationally tailor the materials design by a still rare organic solid-state chemistry. (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH)