Superior Selective CO₂ Adsorption of C₃N Pores: GCMC and DFT Simulations

Development of high-performance sorbents is extremely significant for CO₂ capture due to its increasing atmospheric concentration and impact on environmental degradation. In this work, we develop a new model of C₃N pores based on GCMC calculations to describe its CO₂ adsorption capacity and selectivity. Remarkably, it exhibits an outstanding CO₂ adsorption capacity and selectivity. For example, at 0.15 bar it shows exceptionally high CO₂ uptakes of 3.99 and 2.07 mmol/g with good CO₂/CO, CO₂/H₂, and CO₂/CH₄ selectivity at 300 and 350 K, separately. More importantly, this adsorbent also shows better water stability. Specifically, its CO₂ uptakes are 3.80 and 5.91 mmol/g for and 0.15 and 1 bar at 300 K with a higher water content. Furthermore, DFT calculations demonstrate that the strong interactions between C₃N pores and CO₂ molecules contribute to its impressive CO₂ uptake and selectivity, indicating that C₃N pores can be an extremely promising candidate for CO₂ capture.