# Trade-Off between Adsorption and Regeneration in Functional Metal–Organic Frameworks for Atmospheric Water Harvesting: A Multiscale Modeling Approach

## TL;DR

This study uses multiscale modeling to understand how different functional groups in metal-organic frameworks affect water harvesting and regeneration efficiency.

## Contribution

A multiscale modeling approach is applied to evaluate the trade-off between water adsorption and regeneration in functional MOFs for atmospheric water harvesting.

## Key findings

- Cu–F@MOF-303 shows high water uptake but requires higher regeneration temperatures.
- Cu–Cl@MOF-303 offers a balanced performance with moderate adsorption and energy-efficient regeneration.
- Cu–Br@MOF-303 and Cu–I@MOF-303 increase low-humidity water uptake but need more energy for regeneration.

## Abstract

Understanding the trade-off between water adsorption
and regeneration
efficiency is essential for the rational design of functional metal–organic
frameworks (MOFs) for atmospheric water harvesting (AWH). In this
work, Cu-halide-functionalized MOF-303 is employed as a representative
case study. A multiscale modeling framework combining Grand Canonical
Monte Carlo (GCMC), Kinetic Monte Carlo (KMC), Density Functional
Theory (DFT), and Molecular Dynamics (MD) simulations, along with
a time-dependent thermodynamic analysis, is used to evaluate the impact
of different Cu-halide ligands (F, Cl, Br, and I) on water adsorption–desorption
behavior. Model accuracy is validated through comparison with previously
reported experimental data from the literature for pristine MOF-303,
showing good agreement between simulations and published experimental
results. The results indicate that Cu–F@MOF-303 exhibits strong
electrostatic interactions, leading to high water uptake and rapid
adsorption kinetics, but at the expense of higher regeneration temperatures.
In contrast, Cu–Cl@MOF-303 achieves a more balanced performance,
offering moderate adsorption capacity with comparatively energy-efficient
regeneration. Cu–Br@MOF-303 and Cu–I@MOF-303 enhance
water uptake at low relative humidity (<20%) but require higher
energy input for water release. Overall, this study demonstrates how
targeted functionalization governs the adsorption–regeneration
trade-off in MOFs and provides guidance for the sustainable design
of AWH materials under diverse environmental conditions.