2026-06-23T01:24:01Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/74942024-06-12T11:49:24Zcom_10259_6168com_10259_5086com_10259_2604com_10259_4323col_10259_6169col_10259_4330

00925njm 22002777a 4500 dc Gutiérrez Vega, Alberto author Tamayo Ramos, Juan Antonio author Martel Martín, Sonia author Barros García, Rocío author Bol Arreba, Alfredo author Gennari, Fabiana C. author Larochette, Pierre Arneodo author Atilhan, Mert author Aparicio Martínez, Santiago author 2022-06 Lithium silicates have attracted great attention in recent years due to their potential use as high-temperature (450–700 °C) sorbents for CO2 capture. Lithium orthosilicate (Li4SiO4) can theoretically adsorb CO2 in amounts up to 0.36 g CO2 per g Li4SiO4. The development of new Li4SiO4-based sorbents is hindered by a lack of knowledge of the mechanisms ruling CO2 adsorption on Li4SiO4, especially for eutectic mixtures. In this work, the structural, electronic, thermodynamic and CO2 capture properties of monoclinic phases of Li4SiO4 and a binary (Li3NaSiO4) eutectic mixture are investigated using density functional theory. The properties of the bulk crystal phases as well as of the relevant surfaces are analysed. Likewise, the results for CO2–lithium silicates indicate that CO2 is strongly adsorbed on the oxygen sites of both sorbents through chemisorption, causing an alteration not only in the chemical structure and atomic charges of the gas, as reflected by both the angles and bond distances as well as atomic charges, but also in the cell parameters of the Li4SiO4 and Li3NaSiO4 systems, especially in Li4SiO4(001) and Li3NaSiO4(010) surfaces. The results confirm strong adsorption of CO2 molecules on all the considered surfaces and materials followed by CO2 activation as inferred from CO2 bending, bond elongation and surface to CO2 charge transfer, indicating CO2 chemisorption for all cases. The Li4SiO4 and Li3NaSiO4 surfaces may be proposed as suitable sorbents for CO2 capture in wide temperature ranges. 1463-9076 http://hdl.handle.net/10259/7494 10.1039/d2cp00346e 1463-9084 A theoretical study on CO2 at Li4SiO4 and Li3NaSiO4 surfaces