Enhanced competitive adsorption of CO2 and H2 on
graphyne: A density functional theory study
Hyuk Jae Kwon,
Yongju Kwon,
Taeyoon Kim,
Youngsuk Jung,
Seunggeol Lee,
Min Cho,
Soonchul Kwon
Affiliations
Hyuk Jae Kwon
Energy Lab, Material Research Center, Samsung
Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd, 130
Samsung-ro, Yeongtong-gu, Suwon-si 16678, Republic of Korea
Yongju Kwon
Department of Civil and Environmental Engineering,
Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu,
Busan 46241, Republic of Korea
Taeyoon Kim
Department of Civil and Environmental Engineering,
Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu,
Busan 46241, Republic of Korea
Youngsuk Jung
Film Material Lab, Samsung Advanced Institute of
Technology, Samsung Electronics Co., Ltd., 130 Samsung-ro, Yeongtong-gu,
Suwon-si 16678, Republic of Korea
Seunggeol Lee
Department of Organic Material Science and
Engineering, Pusan, National University, Busan 46241, Republic of
Korea
Min Cho
Division of Biotechnology, Advanced Institute of
Environment and Bioscience, College of Environmental and Bioresource Sciences, Chonbuk
National University, Iksan 54596, Republic of
Korea
Soonchul Kwon
Department of Civil and Environmental Engineering,
Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu,
Busan 46241, Republic of Korea
Adsorption using carbon-based materials has been established to be a feasible method for separating carbon dioxide and hydrogen to mitigate the emission of carbon dioxide into the atmosphere and for the collection of fuel for energy sources, simultaneously. We carried out density functional theory calculation with dispersion correction to investigate the physisorption characteristics of carbon allotropes such as graphene and graphyne for the competitive adsorption of CO2 and H2. It is worth noting that the graphyne represented preferable adsorption energies, short bond lengths and energy charges for both gases, compared with the characteristics observed with graphene. We found that in graphyne, both the affinitive adsorption of CO2, and the competitive adsorption of CO2 and H2, took place at the hollow site between acetylene links, which do not exist in graphene. We demonstrate that in the presence of H2, the CO2 adsorption selectivity of graphyne is higher than that of graphene, because of the improved electronic properties resulting from the acetylene links.
