Adsorption of formaldehyde molecule on the intrinsic and Al-doped graphene: A first principle study

To search for a high sensitivity sensor for formaldehyde (H₂CO), we investigated the adsorption of H₂CO on the intrinsic and Al-doped graphene sheets using density functional theory (DFT) calculations. Compared with the intrinsic graphene, the Al-doped graphene system has high binding energy value and short connecting distance, which are caused by the chemisorption of H₂CO molecule. Furthermore, the density of states (DOS) results show that orbital hybridization could be seen between H₂CO and Al-doped graphene sheet, while there is no evidence for hybridization between the H₂CO molecule and the intrinsic graphene sheet. Therefore, Al-doped graphene is expected to be a novel chemical sensor for H₂CO gas. We hope our calculations are useful for the application of graphene in chemical sensor.