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 CO2 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.

Automated summary

Self-templating is an easy method to synthesize porous carbons through direct pyrolysis of organic metal salts. However, the method usually has low yields and limited specific surface areas due to the low activity of metal cations. In this study, cesium acetate is used as the precursor to produce oxo-carbons with large specific surface areas, high pore volume, adjustable oxygen contents, and high yields. The oxo-carbons show exceptional CO2 uptake and supercapacitor performance. This research helps to understand and design materials using organic solid-state chemistry, which is still rare.