The present development is a method for capturing and purifying CO2 from a flue gas stream using a metal aluminate nanowire absorbent and then regenerating the absorbent. After the CO2 is adsorbed into the absorbent, the adsorbent is regenerated by subjecting the CO2 saturated adsorbent to a dielectric barrier discharge plasma or to a microwave plasma or to a radio frequency (RF) plasma while ensuring that the external temperature does not exceed 200° C.