Highly Porous Carbons Synthesized from Tannic Acid via a Combined Mechanochemical Salt-Templating and Mild Activation Strategy

Highly porous activated carbons were synthesized via the mechanochemical salt-templating method using both sustainable precursors and sustainable chemical activators. Tannic acid is a polyphenolic compound derived from biomass, which, together with urea, can serve as a low-cost, environmentally friendly precursor for the preparation of efficient N-doped carbons. The use of various organic and inorganic salts as activating agents afforded carbons with diverse structural and physicochemical characteristics, e.g., their specific surface areas ranged from 1190 m(2)center dot g(-1) to 3060 m(2)center dot g(-1). Coupling the salt-templating method and chemical activation with potassium oxalate appeared to be an efficient strategy for the synthesis of a highly porous carbon with a specific surface area of 3060 m(2)center dot g(-1), a large total pore volume of 3.07 cm(3)center dot g(-1) and high H-2 and CO2 adsorption capacities of 13.2 mmol center dot g(-1) at -196 degrees C and 4.7 mmol center dot g(-1) at 0 degrees C, respectively. The most microporous carbon from the series exhibited a CO2 uptake capacity as high as 6.4 mmol center dot g(-1) at 1 bar and 0 degrees C. Moreover, these samples showed exceptionally high thermal stability. Such activated carbons obtained from readily available sustainable precursors and activators are attractive for several applications in adsorption and catalysis.

Automated summary

Highly porous activated carbons were synthesized using sustainable precursors and chemical activators through the mechanochemical salt-templating method, showing diverse structural and physicochemical characteristics with specific surface areas ranging from 1190 m(2)center dot g(-1) to 3060 m(2)center dot g(-1). These carbons exhibited high H-2 and CO2 adsorption capacities, with the most microporous carbon showing a CO2 uptake capacity as high as 6.4 mmol center dot g(-1) at 1 bar and 0 degrees C. The activated carbons also displayed exceptional thermal stability, making them attractive for adsorption and catalysis applications.