TY - JOUR
T1 - Exploration of the Synergy Between 2D Nanosheets and a Non-2D Filler in Mixed Matrix Membranes for Gas Separation
AU - Shi, Feng
AU - Sun, Junxia
AU - Wang, Jingtao
AU - Liu, Min
AU - Wang, Shaofei
AU - Cao, Xingzhong
AU - Yan, Zhikun
AU - Li, Yifan
AU - Nunes, Suzana Pereira
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: All authors gratefully acknowledge the financial support from China Scholarship Council and King Abdullah University of Science and Technology, the instrument support from Center of Advanced Analysis & Computational Science, Zhengzhou University. The PALS characterization service, provided by XC and his group (Institute of High Energy Physics, Chinese Academy of Sciences), is also acknowledged.
PY - 2020/2/5
Y1 - 2020/2/5
N2 - Dual-filler MMMs have attracted special interests in recent years because of the possibility of producing synergetic effect. This study is aimed at exploring the underlying synergy between two-dimensional (2D) nanosheets and a non-2D filler in mixed matrix membranes for gas separation. MXene or graphene oxide (GO) as typical nanosheet filler is selected to be in pair with a non-2D filler, SiO2 or halloysite nanotubes (HNTs), with Pebax as the polymer matrix. In this way, four pairs of binary fillers are designed and the corresponding four groups of MMMs are fabricated. By tuning the mass ratio of binary fillers, synergetic effect is found for each group of MMMs. However, the two 2D fillers found different preferential non-2D partners. GO works better with HNTs than SiO2, while MXene prefers SiO2 to HNTs. To be noted, GO/HNTs renders the membranes the maximum enhancement of CO2 permeability (153%) and CO2/N2 selectivity (72%) compared to Pebax control membrane, while each of them as single filler only brought about very limited enhancement of CO2 separation performance. The possible mechanisms are thoroughly discussed in terms of filler dispersion, nanosheet flexibility, and the tortuosity and connectivity of the surface diffusion pathways along nanosheets.
AB - Dual-filler MMMs have attracted special interests in recent years because of the possibility of producing synergetic effect. This study is aimed at exploring the underlying synergy between two-dimensional (2D) nanosheets and a non-2D filler in mixed matrix membranes for gas separation. MXene or graphene oxide (GO) as typical nanosheet filler is selected to be in pair with a non-2D filler, SiO2 or halloysite nanotubes (HNTs), with Pebax as the polymer matrix. In this way, four pairs of binary fillers are designed and the corresponding four groups of MMMs are fabricated. By tuning the mass ratio of binary fillers, synergetic effect is found for each group of MMMs. However, the two 2D fillers found different preferential non-2D partners. GO works better with HNTs than SiO2, while MXene prefers SiO2 to HNTs. To be noted, GO/HNTs renders the membranes the maximum enhancement of CO2 permeability (153%) and CO2/N2 selectivity (72%) compared to Pebax control membrane, while each of them as single filler only brought about very limited enhancement of CO2 separation performance. The possible mechanisms are thoroughly discussed in terms of filler dispersion, nanosheet flexibility, and the tortuosity and connectivity of the surface diffusion pathways along nanosheets.
UR - http://hdl.handle.net/10754/661536
UR - https://www.frontiersin.org/article/10.3389/fchem.2020.00058/full
UR - http://www.scopus.com/inward/record.url?scp=85079679119&partnerID=8YFLogxK
U2 - 10.3389/fchem.2020.00058
DO - 10.3389/fchem.2020.00058
M3 - Article
C2 - 32117883
SN - 2296-2646
VL - 8
JO - Frontiers in Chemistry
JF - Frontiers in Chemistry
ER -