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Abstract This review spotlights the role of atomic‐level modeling in research on metal‐organic frameworks (MOFs), especially the key methodologies of density functional theory (DFT), Monte Carlo (MC) simulations, and molecular dynamics (MD) simulations. The discussion focuses on how periodic and cluster‐based DFT calculations can provide novel insights into MOF properties, with a focus on predicting structural transformations, understanding thermodynamic properties and catalysis, and providing information or properties that are fed into classical simulations such as force field parameters or partial charges. Classical simulation methods, highlighting force field selection, databases of MOFs for high‐throughput screening, and the synergistic nature of MC and MD simulations, are described. By predicting equilibrium thermodynamic and dynamic properties, these methods offer a wide perspective on MOF behavior and mechanisms. Additionally, the incorporation of machine learning (ML) techniques into quantum and classical simulations is discussed. These methods can enhance accuracy, expedite simulation setup, reduce computational costs, as well as predict key parameters, optimize geometries, and estimate MOF stability. By charting the growth and promise of computational research in the MOF field, the aim is to provide insights and recommendations to facilitate the incorporation of computational modeling more broadly into MOF research. 

Abstract Global reliance on fossil fuel combustion for energy production has contributed to the rising concentration of atmospheric CO₂, creating significant global climate challenges. In this regard, direct air capture (DAC) of CO₂from the atmosphere has emerged as one of the most promising strategies to counteract the harmful effects on the environment, and the further development and commercialization of this technology will play a pivotal role in achieving the goal of net‐zero emissions by 2050. Among various DAC adsorbents, metal–organic frameworks (MOFs) show great potential due to their high porosity and ability to reversibly adsorb CO₂at low concentrations. However, the adsorption efficiency and cost‐effectiveness of these materials must be improved to be widely deployed as DAC sorbents. To that end, this perspective provides a critical discussion on several types of benchmark MOFs that have demonstrated high CO₂capture capacities, including an assessment of their stability, CO₂capture mechanism, capture‐release cycling behavior, and scale‐up synthesis. It then concludes by highlighting limitations that must be addressed for these MOFs to go from the research laboratory to implementation in DAC devices on a global scale so they can effectively mitigate climate change. 

Precise control of aperture dimensions is crucial in adsorptive separations of hydrocarbons, as it directly affects key parameters such as selectivity, capacity, diffusion, and recyclability. The development of metal-organic frameworks (MOFs) has enabled the fine-tuning of local pore environments to address important hydrocarbon separations. However, customizing aperture geometry to tune kinetic separation performance remains challenging. Here, we deploy a mixed-linker synthesis strategy, combining long and short linkers on fcu net Zr-MOFs with equilateral triangular apertures to construct isoreticular multivariate MOFs, NU-415 and NU-416, with tailored isosceles triangular apertures suitable for the separation of hexane isomers. Sorption, liquid batch separa-tion and X-ray diffraction measurements demonstrate significantly improved selectivity, capacity, stability and recyclability of NU-415 and NU-416 compared with Zr-muconate and MOF-801. Notably, both NU-415 and NU-416 achieve uptake capacities of 2.2 mmol g-1 in 1 minute with a n-hexane to 2,2-dimethylbutane selectivity over 200 in equimolar ternary mixture at ambient conditions, comparable to leading reported materials. Mechanistic studies confirm that separation performance is predominantly governed by significant kinetic differences rather than by thermodynamics. The successful customization of aperture geometry not only enables superior linear to monobranched hexane selectivity in NU-415, but also demonstrates the mixed-linker synthesis strategy as a promising solution for precise and predictable pore architecture control in MOFs. 

Metal-organic frameworks (MOFs) have been examined extensively for CO2 capture, and the influence of water co-adsorption on these processes is particularly relevant, as CO2 capture generally occurs in humid gas streams. To investi-gate CO2/H2O co-adsorption, binary adsorption isotherms of CO2 and H2O were measured on MOF-808-TFA (TFA = trifluoro-acetic acid). When water was pre-adsorbed on MOF-808-TFA, and a subsequent CO2 adsorption isotherm was measured, the CO2 adsorption was slightly reduced, as expected. However, when CO2 was adsorbed first and then an H2O adsorption iso-therm was measured, no significant H2O adsorption capacity was observed. The near complete loss of water adsorption ca-pacity was observed even when only a trace amount of CO2 was pre-adsorbed. The results show that unexpected, non-state function adsorption equilibria can result from dynamic MOF behaviors and defect sites, which may lead to counterintuitive adsorption data compared to traditional materials. 

Downsizing noble metal catalysts is essential for improving atomic efficiency in sustainable energy applications. Typically, strategies focus on anchoring atomically scaled catalysts onto heteroatom-rich substrates, but these interactions can unintentionally alter the electronic structure of the catalyst, complicating the hydrogen evolution reaction (HER) mechanism. This study focuses on elucidating the interfacial mechanism of HER using structurally well-defined platinum single-atom (Pt SA) electrocatalysts. Unlike chemically reduced SAs, electrochemically deposited Pt SA catalysts do not rely on strong support interactions. As a result, these isolated Pt atoms can potentially achieve the theoretical maximum hydrogen production efficiency. This work introduces electrocatalysts composed solely of true SA sites, clarifying previous ambiguities surrounding the concept of SA electrocatalysis. 

CO₂capture from post-combustion flue gas originating from coal or natural gas power plants, or even from the ambient atmosphere, is a promising strategy to reduce the atmospheric CO₂concentration and achieve global decarbonization goals. However, the co-existence of water vapor in these sources presents a significant challenge, as water often competes with CO₂for adsorption sites, thereby diminishing the performance of adsorbent materials. Selectively capturing CO₂in the presence of moisture is a key goal, as there is a growing demand for materials capable of selectively adsorbing CO₂under humid conditions. Among these, metal–organic frameworks (MOFs), a class of porous, highly tunable materials, have attracted extensive interest for gas capture, storage, and separation applications. The numerous combinations of secondary building units and organic linkers offer abundant opportunities for designing systems with enhanced CO₂selectivity. Interestingly, some recent studies have demonstrated that interactions between water and CO₂within the confined pore space of MOFs can enhance CO₂uptake, flipping the traditionally detrimental role of moisture into a beneficial one. These findings introduce a new paradigm: water-enhanced CO₂capture in MOFs. In this review, we summarize these recent discoveries, highlighting examples of MOFs that exhibit enhanced CO₂adsorption under humid conditions compared to dry conditions. We discuss the underlying mechanisms, design strategies, and structural features that enable this behavior. Finally, we offer a brief perspective on future directions for MOF development in the context of water-enhanced CO₂capture. 

Metal-organic frameworks (MOFs) with tunable structures and unique host-guest chemistry have emerged as promising candidates for conductive materials. However, the tunability of conductivity and porosity in conductive MOFs and their interrelationship still lack a systematic study. Herein, we report the synthesis of a series of 3D copper MOFs (NU-4000 to NU-4003) using a triphenylene-based hexatopic carboxylate linker. By modulating the ratio of mixed solvents, distinct structural topologies and π-π stacking arrangements were achieved, resulting in electrical conductivity ranging from insulators (˂ 10-6 S/cm) to semiconductors (10-8 ~ 102 S/cm). Among them, NU-4003 features continuous π-π stacking and exhibits a conductivity of 1.7 × 10-6 S/cm. To further enhance conductivity, we encapsulated C60, a strong electron acceptor, within the circular channels of NU-4003, resulting in a remarkable conductivity increase to 140 S/cm with approximately 100% pore occupancy. Even at lower C60 loadings that leave 54% of the pore volume remaining accessible, the conductivity remains exceptionally high at 104 S/cm. This represents an eight-order magnitude enhancement and positions NU-4003-C60 as one of the most conductive 3D MOFs reported to date. This work integrates two charge transport pathways (through-space and electron donor and acceptor) into a single MOF host-guest material, achieving a significant enhancement in conductivity. This study demonstrates the potential of combining host-guest chemistry and π-π stacking to design conductive MOFs with permanent porosity maintained, providing a blueprint for the development of next-generation materials for electronic and energy-related applications. 

Global access to drinking water shrinks yearly, yet the atmosphere—our largest sustainable water source—remains largely untapped. Metal–organic frameworks (MOFs), a tunable class of crystalline porous materials, are promising candidates for atmospheric water harvesting. The channel-pore MOF STA-16(Co) stands out due to its robust phosphonate-based structure, which provides high stability and excellent water uptake. However, STA-16(Co) suffers from slow water uptake kinetics. To address this limitation, we introduced defects into STA-16(Co) by selectively removing linkers through treatment with nitrilotriacetic acid, significantly improving water diffusion kinetics. The defective MOFs demonstrate markedly faster water saturation rates—delivering ~50% more water in a 40-minute cycle—while maintaining the same uptake capacity and isothermal behavior as pristine STA-16(Co). Solid-state nuclear magnetic resonance analysis confirms that localized defects enhance efficiency without altering the overall pore geometry. This study presents a straightforward and generalizable strategy to optimize water sorption in channel-based MOFs. 

Escalating carbon dioxide (CO2) emissions have intensified the greenhouse effect, posing a significant long-term threat to environmental sustainability. Direct air capture (DAC) has emerged as a promising approach to achieving a net-zero carbon future, which offers several practical advantages, such as independence from specific CO2 emission sources, economic feasibility, flexible deployment, and minimal risk of CO2 leakage. The design and optimization of DAC sorbents are crucial for accelerating industrial adoption. Metal-organic frameworks (MOFs), with high structural order and tunable pore sizes, present an ideal solution for achieving strong guest-host interactions under trace CO2 conditions. This perspective highlights recent advancements in using MOFs for DAC, examines the molecular-level effects of water vapor on trace CO2 capture, reviews data-driven computational screening methods to develop a molecularly programmable MOF platform for identifying optimal DAC sorbents, and discusses scale-up and cost of MOFs for DAC.