Heteroatom-Enhanced Porous Carbon Materials Based on Polybenzoxazine for Supercapacitor Electrodes and CO2 Capture

Through a solution method utilizing benzoxazine chemistry, heteroatoms containing porous carbons (HCPCs) were synthesized from melamine, eugenol and formaldehyde, followed by carbonization in a nitrogen atmosphere and chemical activation with KOH at three different activation temperatures, 700, 800 and 900 degrees C. The introduction of melamine and eugenol to the monomer produced structurally bonded nitrogen and oxygen in porous carbons. Changing the calcination temperature can alter the doping level of heteroatoms and the particle size. These carbon materials exhibit large pore size distributions, tunable pore structure, high nitrogen and oxygen contents and high surface areas, which make them suitable for use as electrode materials in supercapacitors. As a result of activating at 800 degrees C, the sample HCPC-800 exhibits a high specific surface area of 984 m(2)/g, high oxygen and nitrogen content (3.64-6.26 wt.% and 10.61-13.65 wt.%), hierarchical pore structure, high degree of graphitization and good electrical conductivity. An outstanding rate capability is also demonstrated, as well as incredible longevity, retaining the capacitance up to 83% even after 5000 cycles in a solution containing 1 M H2SO4. Moreover, the activated porous carbon containing nitrogen exhibits a CO2 adsorption capacity of 3.6 and 3.5 mmol/g at 25 degrees C and 0 degrees C, respectively, which corresponds to equilibrium pressures of 1 bar.

Automated summary

HCPCs were synthesized using melamine, eugenol, and formaldehyde and activated at different temperatures. The introduction of melamine and eugenol resulted in bonded nitrogen and oxygen in the porous carbons. The activated carbon materials exhibited suitable properties for electrode materials in supercapacitors, with high surface areas, nitrogen and oxygen contents, and excellent rate capability and longevity. The nitrogen-containing activated porous carbon also showed significant CO2 adsorption capacity.