TY - JOUR
T1 - Density Functional Simulation of Adsorption Behavior within the Dicalcium Silicate-Accelerated Carbonation System
AU - Zhao, Meicheng
AU - Rao, Meijuan
AU - Wang, Fazhou
AU - Tao, Yong
AU - Lu, Linnu
N1 - Funding Information:
Financial support from the National Natural Science Foundation of China (nos. 51925205, 51972249, and 52172026) and the Natural Science Foundation of Hubei Province (no. 2020CFB827) is gratefully acknowledged.
Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
PY - 2022/12/19
Y1 - 2022/12/19
N2 - In this study, the adsorption behavior of various molecules, including H2O, CO2, and H2CO3, on the C2S surface in the carbonation system was systematically compared to elucidate the microscopic mechanism in early accelerated carbonation using density functional theory and ab initio molecular dynamics. The electronic structures on β-C2S and γ-C2S surfaces differ, in that the valence band maximum is contributed by the O p orbital and Ca s orbital, respectively. This difference results in different proton-surface interactions. The protons hydroxylated the [SiO4]4-tetrahedra on the β-C2S surface. On the γ-C2S surface, the protons enter the interior surface to form a three-coordination configuration with Ca atoms in addition to bonding with the [SiO4]4-tetrahedra. The adsorption energy for the dissociative adsorption of H2CO3on both β-C2S and γ-C2S surfaces is significantly higher than that of H2O, and the dissociative adsorption configurations are also more stable. CO2only has a strong adsorption tendency on the γ-C2S surface, where it acquires electrons from the surface Ca atoms to become activated. In the molecular adsorption phase, γ-C2S interacts more strongly with CO2, H2CO3, and its dissociation products. copy; 2022 American Chemical Society.
AB - In this study, the adsorption behavior of various molecules, including H2O, CO2, and H2CO3, on the C2S surface in the carbonation system was systematically compared to elucidate the microscopic mechanism in early accelerated carbonation using density functional theory and ab initio molecular dynamics. The electronic structures on β-C2S and γ-C2S surfaces differ, in that the valence band maximum is contributed by the O p orbital and Ca s orbital, respectively. This difference results in different proton-surface interactions. The protons hydroxylated the [SiO4]4-tetrahedra on the β-C2S surface. On the γ-C2S surface, the protons enter the interior surface to form a three-coordination configuration with Ca atoms in addition to bonding with the [SiO4]4-tetrahedra. The adsorption energy for the dissociative adsorption of H2CO3on both β-C2S and γ-C2S surfaces is significantly higher than that of H2O, and the dissociative adsorption configurations are also more stable. CO2only has a strong adsorption tendency on the γ-C2S surface, where it acquires electrons from the surface Ca atoms to become activated. In the molecular adsorption phase, γ-C2S interacts more strongly with CO2, H2CO3, and its dissociation products. copy; 2022 American Chemical Society.
KW - ab initio calculation
KW - adsorption
KW - carbonation
KW - dicalcium silicate
KW - thermodynamic
UR - http://www.scopus.com/inward/record.url?scp=85144536984&partnerID=8YFLogxK
U2 - 10.1021/acssuschemeng.2c05321
DO - 10.1021/acssuschemeng.2c05321
M3 - Journal article
AN - SCOPUS:85144536984
SN - 2168-0485
VL - 10
SP - 16825
EP - 16832
JO - ACS Sustainable Chemistry and Engineering
JF - ACS Sustainable Chemistry and Engineering
IS - 50
ER -