A Hydrogen‐Bonded Organic Framework (HOF) with Type IV NH₃Adsorption Behavior

Abstract

An S‐shaped gas isotherm pattern displays high working capacity in pressure‐swing adsorption cycle, as established for CO2, CH4, acetylene, and CO. However, to our knowledge, this type of adsorption behavior has not been revealed for NH3 gas. Herein, we design and characterize a hydrogen‐bonded organic framework (HOF) that can adsorb NH3 uniquely in an S‐shape (type IV) fashion. While conventional porous materials, mostly with type I NH3 adsorption behavior, require relatively high regeneration temperature, this platform which has significant working capacity is easily regenerated and recyclable at room temperature.

Highly Dispersed Ionic Liquids in Mesoporous Molecular Sieves Enable a Record NH3 Absorption

“…Moreover, the capacity of [C 1 NH 3 ]­[Zn 3 Cl 7 ]@FDU-12-60% was also higher than the typical porous adsorbents such as MOF, COF, HOF, and acidic porous polymers (Table S2), which indicates that this hybrid material is an efficient NH 3 adsorbent. Compared with the porous adsorbents reported in the literatures, ,,,− the adsorption capacity of [C 1 NH 3 ]­[Zn 3 Cl 7 ]@FDU-12-60% is a record (Figure b).…”

“…(a) NH 3 adsorption isotherms of FDU-12 and ZnIL@FDU-12- x hybrids at 25.0 °C; (b) NH 3 uptake capacity of some typical porous adsorbents reported in the literature and in this work, Mg 2 (dobpdc), KUF-1, Cu 2 Cl 2 BBTA, MFM-300, COF-10, P1-PO 3 H 2 , CoHCC; (c) NH 3 uptake capacity of neat [C 1 NH 3 ]­[ZnCl 3 ] and dispersed [C 1 NH 3 ]­[ZnCl 3 ] in ZnIL@FDU-12-60% at different partial pressures; (d) NH 3 adsorption isotherms of [C 1 NH 3 ]­[Zn 3 Cl 7 ]@FDU-12-60% at 80.0, 100, and 120 °C.…”

“…Energy-efficient adsorption separation has received intensive attention in NH 3 capture in the past few decades, which promotes the development of many functional adsorbents. − Thus, not only traditional adsorbents like porous carbons, mesoporous silica, and zeolites − but also novel porous materials such as metal–organic frameworks (MOFs), covalent organic frameworks (COFs), and hydrogen organic frameworks (HOFs) ,,− have been used for NH 3 capture. In general, there are two main challenges in NH 3 capture by solid porous adsorbents.…”

Hybrid Nafion Membranes of Ionic Hydrogen-Bonded Organic Framework Materials for Proton Conduction and PEMFC Applications

“…In the past 2 decades, crystalline materials, such as metal–organic frameworks (MOFs), covalent organic frameworks (COFs), or hydrogen-bonded organic frameworks (HOFs), have attracted extensive attention because of their unlimited structural diversity and functional tunability. − Due to the ability to custom-design the ligands with carrier molecules, tailor pore environments, and understand proton-transport pathways at the molecular level, crystalline materials provide a new platform for proton-conducting materials. − However, most of these crystalline materials focus on the conduction of crystals, the research studies on PEMs and PEMFCs are rare. ,− Owing to the unique characteristics such as rich hydrogen-bonding network and solution machinability, crystalline HOFs render a promising platform for proton conductivity and PEM materials. − The ligands used to construct single-component HOFs such as −COOH and −NH 2 can use their own functional groups to form hydrogen bonds, − but these traditional HOFs connected by weak hydrogen bonds have poor stability and, in most cases, the structures collapse under medium and high temperature conditions. Different from single-component HOFs, ionic two-component HOFs (also known as charge-assisted hydrogen bond frameworks) showed good stability due to the various hydrogen bond types and electrostatic interactions.…”

Regulated Threshold Pressure of Reversibly Sigmoidal NH3 Absorption Isotherm with Ionic Liquids

“…22,26 S mode is considered as one of the potential approaches for gas adsorption at low concentrations; however, the application in NH 3 capture is quite limited for the sorbents suffering from NH 3 . 19,27,28 ILs are considered as an alternative to NH 3 as well as other gas absorption for their feasible designing and structure modification. ILs as well as DES functionalized with the hydroxyl group such as [EtOHmim], 18 [choline], 29 glycerol, 30 and amine group 31 were reported to NH 3 absorption through hydrogen bonding.…”