Abstract
Porous organic salts (POSs) are an emerging class of materials with ordered ionic architectures, offering excellent proton transfer and water uptake properties. However, conventional POS synthesis via strong acid–base neutralization (e.g., ─SO₃H and ─NH₂) leads to extensive hydrogen bonding with water, compromising stability in aqueous and water-lean environments. Here, we address this challenge by designing POSs with hydrophobic porous channels and minimal hydrogen bonding formation. Our key innovation is the use of fluorinated tetrazole as a weak acid tecton and a tetra-substituted imidazole precursor devoid of active protons as the base. Single-crystal analysis and computational modeling reveal that the structural integrity of the synthesized POSs arises primarily from cation–anion interactions, with water confined as clusters in the pores, independent of hydrogen bonding with the scaffold. Robustness of the POS structure under aqueous and water-lean conditions is confirmed by X-ray and neutron scattering, as well as computational modeling, confirming preserved packing and crystal structures. The stability of POS is further demonstrated in aqueous iodine capture, with imidazolium cations and C–F functionalizations serving as strong adsorption sites. The approach developed herein further pushes the boundary of POS materials to withstand both aqueous and water-lean conditions.
| Original language | English |
|---|---|
| Article number | e202510966 |
| Journal | Angewandte Chemie - International Edition |
| Volume | 64 |
| Issue number | 37 |
| DOIs | |
| State | Published - Sep 8 2025 |
Funding
The research was supported financially by the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences, US Department of Energy. This research used resources at the High Flux Isotope Reactor, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory (IPTS‐33565 and 32388). This research was performed on APS beam time award, https://doi.org/10.46936/APS‐188511/60013158 , from the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science user facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE‐AC02‐06CH11357. Solid‐state NMR experiments were supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences, Materials Science and Engineering Division. The research was performed at the Ames Laboratory, which is operated for the U.S. DOE by Iowa State University under contract # DE‐AC02‐07CH11358. This research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. The beam time was allocated to VISION (IPTS‐35024.1).
Keywords
- Fluorinated tecton
- Hydrogen bonding
- Porous organic salts
- Thermal stability
- Water stability