Experimental and modelling studies of carbon dioxide capture onto pristine, nitrogen-doped, and activated ordered mesoporous carbons.

The search for suitable materials for carbon dioxide capture and storage has attracted the attention of the scientific community in view of the increased global CO2 levels and its after-effects. Among the different materials under research, porous carbons and their doped analogues are extensively debated for their ability to store carbon dioxide at high pressures. The present paper examined high-pressure carbon dioxide storage studies of 1-D hexagonal and 3-D cubic ordered mesoporous pristine and N-doped carbons prepared using the nano-casting method. Excess carbon dioxide sorption isotherms were obtained using the volumetric technique and were fitted using the Toth model. Various parameters that influence CO2 storage on metal-free ordered mesoporous carbons, such as the effect of pore size, pore dimension, pyrolysis temperature, the impact of nitrogen substitution, and the effect of ammonia activation are discussed. It was observed that the carbon dioxide storage capacity has an inverse relation to the total nitrogen doped, the amount of pyridinic nitrogen functionality, and the pyrolysis temperature, whereas the pore size seems to have a linear relationship. On the other hand, the presence of oxygen has a positive effect on the sorption capacity. Among the prepared ordered mesoporous carbons, the ammonia-treated one has shown the highest adsorption capacity of 37.8 mmol g-1 at 34 bar and 0 °C.

Electrochemical performance of nano-sized LiFePO4-embedded 3D-cubic ordered mesoporous carbon and nitrogenous carbon composites.

Herein, we report a single-step synthesis, characterization, and electrochemical performance of nano-sized LiFePO4 (LFP)-embedded 3D-cubic mesoporous carbon (CSI-809) and nitrogenous carbon (MNC-859) composites. Furthermore, in order to investigate the effects of both CSI-809 and MNC-859 on the electrochemical characteristics of LFP, a systematic study was performed on the morphology and microstructure of the composites, viz., LFP/CSI-809 and LFP/MNC-859, using XRD, FE-SEM, FT-Raman, and BET surface area analyses. Among these composites, LFP/MNC-859 exhibited better electrochemical performance with higher specific capacity and rate capability as compared to those of LFP/CSI-809. In addition, even after 100 cycles, LFP/MNC-859 retained 97% of its initial discharge capacity at 1C rate. The enhanced electrochemical performance of the nano-sized LFP-embedded MNC-859 can be attributed to the conductive nitrogenous carbon and mesoporosity, which facilitate electrolyte diffusion, and improved conductivity of the advanced LFP-nitrogenous porous carbon matrix.