Recyclable switching between nonporous and porous phases of a square lattice (sql) topology coordination network

Abstract

A nonporous square lattice (sql) coordination network [Co(bipy)2(NCS)2]n (sql-1-Co-NCS) exhibits recyclable switching induced by CO2. The sorption isotherms are stepped with moderate hysteresis, temperature controlled and saturation uptake is fixed. Such switching, which has rarely been observed, offers the promise of exceptional working capacity for gas storage.

Highly Selective, High‐Capacity Separation of o‐Xylene from C8 Aromatics by a Switching Adsorbent Layered Material

“…The adsorption properties of sql coordination networks remain underexplored with the notable exception of the so‐called ELM family, which exhibits single or multi‐step gas adsorption isotherms triggered by appropriate stimuli . Recently, we reported that the related compound sql‐1‐Co‐NCS exhibits recyclable switching with single‐step adsorption isotherms induced by CO 2 . These switchable sql coordination networks, which we termed switching adsorbent layered materials, have not yet been studied with respect to their sorption properties on hydrocarbon vapors and liquids, although several nonporous organic solids showed promising selectivity signatures .…”

“…The nonporous (closed) phase [Co(bipy) 2 (NCS) 2 ] n ( sql‐1‐Co‐NCS ) was prepared using the method described recently . Single crystals of the open phases of sql‐1‐Co‐NCS were prepared via solvent diffusion: sql‐1‐Co‐NCS⋅4PX , sql‐1‐Co‐NCS⋅4MX , sql‐1‐Co‐NCS⋅4OX and sql‐1‐Co‐NCS⋅2EB (PX= para ‐xylene, MX= meta ‐xylene, OX= ortho ‐xylene, EB=ethylbenzene; full synthesis procedures are given in Supporting Information).…”

“…Sorption of four xylene molecules per formula unit results in interlayer separations increasing from 4.5 Å (closed phase) to about 9.2 Å (xylene‐loaded phases) and a doubling of unit‐cell volume. A literature review revealed that these phases exhibit the largest interlayer separations yet seen among bipy‐based sql coordination networks (Supporting Information, Table S5).…”

Crystal engineering of a rectangular sql coordination network to enable xylenes selectivity over ethylbenzene

“…At 195 K, sql-1-Co-NCS was reported to exhibit a switching or Type F-IV 21 CO 2 sorption isotherm at low pressure. 49 sql-1,3-Co-NCS, was also observed to exhibit a stepped isotherm (Fig. 3a and S22 †) with low CO 2 uptake until ca.…”

Highly Selective, High‐Capacity Separation of o‐Xylene from C8 Aromatics by a Switching Adsorbent Layered Material

“…Herein, we describe an ew approach to C 8 aromatics separation that, counterintuitively,involves the use of anonporous material, [17] {[Co(4,4'-bipyridine) 2 (NCS) 2 ]} n (sql-1-Co-NCS), which switches to open phases when exposed to certain guests ( Figure 1). sql-1-Co-NCS belongs to abroad family of MOMs comprised of octahedral metal ions, M,c oordinated counter anions, A,a nd linear linker ligands, L.W hen M:L is 1:2then square lattice (sql)coordination networks of formula {[M(L) 2 (A) 2 ]·xguest} n are readily formed.…”