A new-style two-dimensional C₃N monolayer, unlike the honeycomb C₃N monolayer, is proposed as a gas sensor, capture and separation. By using the first-principles method, the adsorption behaviors of gas molecules (NH₃, H₂S, SO₂, CO, CO₂, NO, NO₂, CH₄, HCN, N₂, H₂ and O₂) on the C₃N monolayer were investigated, and the charge density difference, density of state and Hirshfeld charge of those adsorption systems were also discussed. The results show that the SO₂ and NO₂ are chemisorbed on the C₃N nanosheet with large adsorption strength, while the other gases are adsorbed by weak physisorption. The analysis of charge density difference and density of state suggests that SO₂ and NO₂ gain much charge from C₃N sheet, and the hybridizations between C₃N sheet and SO₂/NO₂-p orbitals lead to strong gas-adsorbent interactions. The recovery time of SO₂ and NO₂ is predicted to be 7.47 × 10⁻⁴ s and 15.91 s at room temperature. Additionally, the CO₂ can be captured and separated from the mixtures of CO₂, NH₃, H₂S, CO, CH₄, H₂ through injecting two electrons into C₃N sheet. Therefore, the new C₃N nanosheet can be a promising bifunctional material as SO₂, NO₂ sensor and CO₂ separation.

与蜂窝状的C ₃ N单层不同，提出了一种新型的二维C ₃ N单层作为气体传感器，捕获和分离方法。通过第一原理方法，气体分子（NH ₃，H ₂ S，SO ₂，CO，CO ₂，NO，NO ₂，CH ₄，HCN，N ₂，H ₂和O ₂）的吸附行为研究了C ₃ N单层，并讨论了这些吸附体系的电荷密度差，状态密度和Hirshfeld电荷。结果表明，SO ₂和NO ₂它们被化学吸附在具有较大吸附强度的C ₃ N纳米片上，而其他气体则通过弱物理吸附而被吸附。电荷密度差和状态密度的分析表明，SO ₂和NO ₂从C ₃ N片中获得大量电荷，并且C ₃ N片与SO ₂ / NO ₂ -p轨道之间的杂化导致强烈的气体-吸附剂相互作用。 室温下SO ₂和NO ₂的回收时间预计为7.47×10 ^-4 s和15.91 s。另外，可以捕获CO ₂并将其与CO ₂的混合物分离通过将两个电子注入C ₃ N薄板中，获得NH ₃，H ₂ S，CO，CH ₄，H ₂。因此，新的C ₃ N纳米片可以作为SO ₂，NO ₂传感器和CO ₂分离的有前途的双功能材料。