| Summary: | LiTiO<sub>2</sub> was prepared from tetraethoxy titanium and lithium ethoxide by a sol–gel process and then treated at 773 K and 973 K under oxygen atmosphere, respectively. Compared with LiTiO<sub>2</sub> prepared at 973 K, LiTiO<sub>2</sub> prepared at 773 K has better CO<sub>2</sub> capture properties. XRD patterns of synthetic LiTiO<sub>2</sub> before and after CO<sub>2</sub> capture confirm that the intermediate product, Li<sub>x</sub>Ti<sub>z</sub>O<sub>2</sub>, is produced during CO<sub>2</sub> capture. CO<sub>2</sub> absorption degree of LiTiO<sub>2</sub> was determined to be 37% (293 K), 40.8% (333 K), 45.5% (373 K), and 50.1% (393 K) for 11.75 h, respectively. Repetitive CO<sub>2</sub> capture experiment indicates that LiTiO<sub>2</sub> has excellent cyclic regeneration behavior. The CO<sub>2</sub> absorption degree of LiTiO<sub>2</sub> increased with increasing CO<sub>2</sub> concentration. At a concentration of 0.05%, the absorption degree of LiTiO<sub>2</sub> had a stable value of 1% even after an absorption time of 1.4 h. LiBO<sub>2</sub> was fabricated by the similar sol–gel method and treated at 713 K. Mass percentage and specific surface area of synthesized LiBO<sub>2</sub> increased with the increasing absorption temperature. Evidently, the diffusion of the CO<sub>2</sub> molecule through the reaction product, which had a low activation energy of 15 kJ·mol<sup>−1</sup> and apparent specific surface value of 55.63 m<sup>2</sup>/g, determined the efficiency of the absorption reaction. Compared with the other sol–gel synthesized lithium-based oxides, LiTiO<sub>2</sub> possessed higher absorption capabilities and lower desorption temperature.
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