Doping of Calcium in C60 Fullerene for Enhancing CO2 Capture and N2O Transformation: A Theoretical Study

Recently, capturing or transforming greenhouse gases, such as CO2 and N2O, have attracted considerable interest from the perspective of environmental protection. In the present work, by studying CO2 and N2O adsorption on pristine and calcium (Ca)-decorated fullerenes (C-60) with density functional theory (DFT) methods, we have evaluated the potential application of this C-60-based complex for the capture of CO2 and transformation of N2O. The results indicate that the adsorptions of CO2 and N2O molecules on the pristine C-60 are considerably weak accompanied by neglectable charge transfer. When C-60 is decorated with Ca atoms, however, it is found that CO2 and N2O adsorptions on the C-60 are greatly enhanced. Up to five CO2 molecules can be adsorbed on the CaC60 system due to the electrostatic interaction. For N2O molecule, it is first molecularly adsorbed on the Ca atom with the adsorption energy of -0.534 eV, followed by the N-2 formation with a low barrier and high exothermicity. Moreover, when four Ca atoms are decorated on the surface of C-60, the maximum number of the adsorbed CO2 molecules is 16. Our results might be useful not only to widen the potential applications of fullerene but also to provide an effective method to capture or transform greenhouse gases.