Abstract
Theoretical calculations based on the Density Functional Theory (DFT) have been performed to investigate the interaction of H
2
S as well SO
2
gaseous molecules at the surfaces of Be
12
O
12
and Mg
12
O
12
nano-cages. The results show that a Mg
12
O
12
nano-cage is a better sorbent than a Be
12
O
12
nano-cage for the considered gases. Moreover, the ability of SO
2
gas to be adsorbed is higher than that of H
2
S gas. The HOMO–LUMO gap (E
g
) of Be
12
O
12
nano-cage is more sensitive to SO
2
than H
2
S adsorption, while the E
g
value of Mg
12
O
12
nano-cage reveals higher sensitivity to H
2
S than SO
2
adsorption. The molecular dynamic calculations show that the H
2
S molecule cannot be retained at the surface of a Be
12
O
12
nano-cage within 300–700 K and cannot be retained on a Mg
12
O
12
nano-cage at 700 K, while the SO
2
molecule can be retained at the surfaces of Be
12
O
12
and Mg
12
O
12
nano-cages up to 700 K. Moreover, the thermodynamic calculations indicate that the reactions between H
2
S as well SO
2
with Be
12
O
12
and Mg
12
O
12
nano-cages are exothermic. Our results suggest that we can use Be
12
O
12
and Mg
12
O
12
nano-cages as sorbents as well as sensors for H
2
S and SO
2
gases.