posted on 2024-01-19, 13:05authored byKaiyuan Zhou, Jingjing Zhang, Yuan Geng, Pengfu Gao, Yi Xie, Jinqiao Dong, Yongjia Shang, Yong Cui, Wei Gong
Physical separation of acetylene
(C2H2) from
carbon dioxide (CO2) or ethylene (C2H4) on metal–organic frameworks (MOFs) is crucial for achieving
high-purity feed gases with minimal energy penalty. However, such
processes are exceptionally challenging due to their close physical
properties and are also critically restricted by the high cost of
large-scale MOF synthesis. Here, we demonstrate the readily scalable
synthesis of a highly water-resistant chiral Cu-MOF (TAMOF-1) based on an inexpensive proteogenic amino acid derivative bearing
rich N/O sites. Notably, the unique coordination in this ultramicroporous
MOF has resulted in the generation of rare global negative electrostatic
potentials, which greatly facilitate the electrostatic interactions
with C2H2 molecules, thus leading to their efficient
separation from C2H2/CO2 and C2H2/C2H4 mixtures under ambient
conditions. The separation efficiency and mechanism are unequivocally
validated by breakthrough experiments and computational simulations.
This work not only highlights the pivotal role of creating a negative
electro-environment in confined spaces for boosting C2H2 capture and separation but also opens up new ways of employing
cheap amino acid derivatives bearing rich electro-negative N and O
sites as organic linkers to constructing high-performing MOF materials
for gas separation purposes.