MOF Linker Extension Strategy for Enhanced Atmospheric Water Harvesting

Abstract

A linker extension strategy for generating metal− organic frameworks (MOFs) with superior moisture-capturing properties is presented. Applying this design approach involving experiment and computation results in MOF-LA2-1 {[Al(OH)-(PZVDC)], where PZVDC 2− is (E)-5-(2-carboxylatovinyl)-1Hpyrazole-3-carboxylate}, which exhibits an approximately 50% water capacity increase compared to the state-of-the-art water-harvesting material MOF-303. The power of this approach is the increase in pore volume while retaining the ability of the MOF to harvest water in arid environments under long-term uptake and release cycling, as well as affording a reduction in regeneration heat and temperature. Density functional theory calculations and Monte Carlo simulations give detailed insight pertaining to framework structure, water interactions within its pores, and the resulting water sorption isotherm.

Shaping the Water-Harvesting Behavior of Metal–Organic Frameworks Aided by Fine-Tuned GPT Models

“…This empirical evidence is in agreement with prior computational predictions on SBU formation and linker configurations (Supporting Information, Section S11). This alignment substantiates the validity of our PXRD simulated patterns and bolsters our confidence in constructing analogous models for the entire LAMOF series (Supporting Information, Sections S4 and S11).…”

“…Finally, we compare the water adsorption behavior of LAMOF-1 and LAMOF-3, which exhibit an alternating cis – trans corner-sharing Al-rod SBU and pore sizes of 8.9 and 8.5 Å, respectively. The primary water molecules bind strongly to the pyrazole groups of the linker and μ 2 -(OH) rod in LAMOF-1 by forming up to three hydrogen bonds (binding energy = −84 to −57 kJ mol –1 ) . In contrast, water molecules adsorb in LAMOF-3 through hydrogen bond interactions with the μ 2 -(OH) rod and O carboxylate groups of the MOF (binding energy = −57 to −52 kJ mol –1 ) and do not interact strongly with the S linker group of the aromatic linker (Figure S88).…”

“…Metal–organic frameworks (MOFs) have shown great promise as sorbents for atmospheric water harvesting. − While earlier research has produced MOFs with success in field tests to produce potable water under desert environments, − the task of designing new and better performing water-harvesting MOFs is complex and labor-intensive. − In addition to limited guiding principles on searching for candidate linkers, − the permutations for linker structural variations are virtually infinite, even when starting with a known effective linker. , This complexity transforms the manual search for new MOF variants as candidate water-harvesting sorbents into a daunting and time-consuming endeavor.…”

ChatGPT Chemistry Assistant for Text Mining and the Prediction of MOF Synthesis

“…We then created a dictionary linking each unique PubChem Compound identification number (CID) or Chemical Abstracts Service (CAS) number to multiple full names and abbreviations and generated the corresponding SMILES code. We note that for complicated linkers or those with missing full names, inappropriate nomenclature, or nonexistent CID or CAS numbers, − manual intervention was occasionally necessary to generate SMILES codes for such chemicals (Supporting Information, Figures S50–S54). However, most straightforward cases were handled efficiently by ChatGPT’s generated Python code.…”

Pore Engineering for High Performance Porous Materials

“…Omar M. Yaghi and his colleagues employed a linker extension strategy to construct a novel MOF with enhanced water harvesting ability . They selected MOF-303, which uses 1 H -pyrazole-3,5-dicarboxylate (PZDC) as the ligand unit, and introduced a molecule called ( E )-5-(2-carboxylatovinyl)-1 H -pyrazole-3-carboxylate, which has an additional ethylene group, to replace PZDC.…”