Abstract: A series of sodium-magnesium double-salt as CO₂ absorption materials with controllable morphologies were prepared by simple mixing method using sodium carboxymethyl cellulose as morphology-directing agent, and then characterized by XRD, SEM and TG. Finally, their CO₂ absorption capability was evaluated by both saturation absorption tests at fixed temperature and dynamic absorption-desorption cyclic experiments. A uniform nanosheet-assembled absorbent, with 0.3 g sodium carboxymethyl cellulose added during preparation, can be obtained with a saturated absorption capacity of 22.8%. Meanwhile, good recycling capacity has been maintained at about 9.7% without apparent changes even after 20 cycles of dynamic absorption-desorption experiment.