Modified Metal-Organic Framework by a Novel Coordinatively Unsaturated Amine Grafting Mechanism for Direct Air Capture of Co2

•Modified MOFs by grafting process between metal sites and secondary amines of AEEA.•Carrier with high surface area, pore volume, and low acidity are deemed preferable.•Excellent thermal/cold stability, and kinetics performance in DAC are obtained.•Direct air CO2 capture cycles with low energy consumption were established.