Synthesis of Highly Porous Coordination Polymers with Open Metal Sites for Enhanced Gas Uptake and Separation

Abstract

Metal-containing amorphous microporous polymers are an emerging class of functional porous materials in which the surface properties and functions of polymers are dictated by the nature of the metal ions incorporated into the framework. In an effort to introduce coordinatively unsaturated metal sites into the porous polymers, we demonstrate herein an aqueous-phase synthesis of porous coordination polymers (PCPs) incorporating bis(o-diiminobenzosemiquinonato)-Cu(II) or -Ni(II) bridges by simply reacting hexaminotriptycene with CuSO·5HO [Cu(II)-PCP] or NiCl·6HO [Ni(II)-PCP] in HO. The resulting polymers showed surface areas of up to 489 m g along with a narrow pore size distribution. The presence of open metal sites significantly improved the gas affinity of these frameworks, leading to an exceptional isosteric heat of adsorption of 10.3 kJ·mol for H at zero coverage. The high affinities of Cu(II)- and Ni(II)-PCPs toward CO prompted us to investigate the removal of CO from natural and landfill gas conditions. We found that the higher affinity of Cu(II)-PCP compared to that of Ni(II)-PCP not only allowed for the tuning of the affinity of CO molecules toward the sorbent, but also led to an exceptional CO/CH selectivity of 35.1 for landfill gas and 20.7 for natural gas at 298 K. These high selectivities were further verified by breakthrough measurements under the simulated natural and landfill gas conditions, in which both Cu(II)- and Ni(II)-PCPs showed complete removal of CO. These results clearly demonstrate the promising attributes of metal-containing porous polymers for gas storage and separation applications.

Molecular complexes and main-chain organometallic polymers based on Janus bis(carbenes) fused to metalloporphyrins

“…57 However, the average pore-size was evaluated at ~3.1 nm, indicating the presence of both micro-and mesopores in Znmat. 20,31,58 Preliminary (Figure 7a). Plots of ln(A0/A) vs. time represented in Figure 7b confirm the first order kinetics of this photooxidation process.…”

“…29 They are also of great interest for the preparation of molecular materials such as main-chain organometallic polymers (MCOPs) (Figure 1). [30][31][32][33] Such materials could be obtained with triptycene-based tris(NHCs) 32 and tetraphenylmethane tetrakis(NHCs) 31 ligands through the formation of CNHC-Pd-CNHC bonds, for example. Peris and coworkers prepared MCOPs with triphenylene-based tris(NHCs) ligands through the formation of CNHC-Au-Cacetylide bonds.…”

N-Donor-Functionalized Acetylacetones for Heterobimetallic Coordination Polymers, the Next Episode: Trimethylpyrazoles

“…Over the last decades coordination polymers (CPs) have attracted increasing interest in various fields of research 1−5 due to their applications in catalysis, 6−8 gas storage and separation, 9,10 and optical properties. 11−13 They can combine high porosity and stability, 14,15 which enables their relevance for industrial processes and competition with industry standards such as zeolites.…”

“…Over the last decades coordination polymers (CPs) have attracted increasing interest in various fields of research − due to their applications in catalysis, − gas storage and separation, , and optical properties. − They can combine high porosity and stability, , which enables their relevance for industrial processes and competition with industry standards such as zeolites. − Since CPs can incorporate a broad variety of elements and take advantage of element-specific properties, e.g. the luminescence of lanthanides, , it is advantageous to combine two or more different metal cations in a single CP.…”

BODIPY‐Based Porous Organic Polymers: How the Monomeric Methyl Substituents and Isomerization Affect the Porosity and Singlet Oxygen Generation

“…In recent years, porous organic polymers (POPs) have shown promising applications in various fields such as photocatalysis, solar cell, CO 2 capture, hydrogen storage, and so on for their advantages in the intrinsic porosity, thermal stability, narrow pore distribution, and low density. Various conjugated POPs have been developed by carbon–carbon cross‐coupling reactions such as Suzuki coupling reaction, Sonogashira coupling reaction, and Yamamoto coupling reaction .…”