Effect of Exposed Facets and Oxidation State of CeO<sub>2</sub> Nanoparticles on CO<sub>2</sub> Adsorption and Desorption
Gimyeong Seong, Akira Yoko, Takaaki Tomai, Takashi Naka, Haodong Wang, Anatoly I. Frenkel, Tadafumi Adschiri
Abstract
CeO 2 nanoparticles exhibit potential as solid adsorbents for carbon dioxide (CO 2 ) capture and storage (CCS), offering precise control over various facets and enhancing their efficiency. This study investigated the adsorption and desorption behaviors of two types of CeO 2 nanoparticles: cubic CeO 2 with primarily {001} facets and polyhedral CeO 2 with mainly {111} facets. The results showed that despite polyhedral CeO 2 ’s lower quantity, it demonstrated successful adsorption–desorption cycles in both oxidized and reduced states. However, reduced CeO 2– x exhibited a higher adsorption capacity but displayed irreversible adsorption–desorption cycles. Reversible adsorption occurred through weak bond formation with CO 2, while cubic CeO 2 with a high oxygen vacancy concentration exhibited irreversible adsorption due to strong bond formation. These insights contribute significantly to understanding CeO 2 nanoparticle characteristics and their impact on the CO 2 adsorption and desorption processes, aiding in the development of advanced CCS techniques.