▎ 摘　　要

The mechanism of ethylenediamine (EDA) grafting on graphene oxides (GO) for CO2 capture is investigated in detail by Quantum chemical calculation. Theoretical results show that, for epoxy on GO, EDA can be grafted via attacking activated C atoms which are adjacent to epoxy, while for carboxyl, EDA can be grafted via attacking C atom of carboxyl directly, and the grafting reaction can be catalyzed by H2O and EDA. The activation energy of EDA grafting on carboxyl (23.2 kcal/mol) is lower than that on epoxy (28.6 kcal/mol), which indicates that carboxyl can be grafted more easily. Moreover, the activation energy of EDA de-grafting on carboxyl (50.7 kcal/mol) is much higher than that on epoxy (19.8 kcal/mol), which indicates that the thermal stability of EDA-carboxyl-grafted GO is much better. This illuminates that carboxyl can be grafted more effectively. The EDA grafting ability of oxygen functional groups on GO is that: carboxyl > epoxy > hydroxyl. The stronger the oxidizing ability of functional groups, the stronger the ability of amine grafting to functional groups.