DFT study on the sensitivity of open edge graphene toward CO2 gas

• CO2 sensing by cleaved graphene is studied by DFT.
• Cleaved graphene can detect CO2 gas.
• Zigzag edges are more sensitive and proper for CO2 detection.
• Our findings are in agreement with experimental results.

We investigated the sensitivity and reactivity of open edge zigzag and armchair graphene slabs toward CO2 gas, using density functional theory calculations. Different levels of theory (B3LYP, ωB97xD, and Minnesota 06 functionals) and basis sets were employed. The results reproduce and explain the electrical behavior which has been observed experimentally from the graphene upon the exposure to the CO2 gas. We found that, unlike the pristine graphene, the open edge graphene layers may be promising chemical sensor for the CO2 detection in agreement with the experimental results. Zigzag edges are more sensitive and reactive than the armchair types.