Andrea Darù

Electrocatalytic hydrogenation (e -H) provides a sustainable route for converting unsaturated organic substrates under mild conditions using renewable electricity as the driving force. Here, we report an MOF-derived cobalt catalyst for the e -H of acetone and pyridine. A new two-dimensional cobalt metal–organic framework, Co-L0-NS, composed of Co(II) nodes and polyaromatic carboxylate linkers, was synthesized as nanosheets and used as a precursor to generate the active catalyst under cathodic bias. Electrochemical pretreatment induces controlled framework reconstruction to form MD-Cat, a highly dispersed, structurally disordered, Co(OH)2-rich nanocluster material. MD-Cat catalyzes the e -H of acetone to isopropanol with nearly quantitative Faradaic efficiency at optimized potentials and promotes pyridine hydrogenation to piperidine with up to 50% Faradaic efficiency. Comparative studies with electrodeposited cobalt, commercial cobalt nanoparticles, and bulk Co(OH)2 show that the MOF-derived catalyst exhibits superior current densities and product selectivity, which we attribute to its nanoscale morphology and hydroxylated cobalt environment. In situ Co K-edge XAS, XPS, PXRD, ATR-SEIRAS, and STEM analyses indicate that Co remains predominantly in the +2 oxidation state during catalysis while undergoing structural reorganization. Tafel analysis supports a PCET-type mechanism for acetone hydrogenation; while DFT calculations suggest that the Co/Co(OH)2 interface suppresses HER by weakening H* binding while preserving organic-substrate activation. These results highlight MOF-templated electrochemical reconstruction as a promising approach for designing selective e -H catalysts, not only by increasing catalyst accessibility through nanostructuring but also by enabling the formation of unique catalytic motifs that would otherwise be difficult to access using traditional methods.

We report an end-to-end computational-experimental workflow for the discovery of metal–organic frameworks (MOFs), demonstrated by the computational design and synthesis of two novel Zn-based frameworks, UCHI-1 and UCHI-2, exhibiting enhanced methane uptake and selectivity at low pressure under ambient conditions (298 K, 1 bar). The workflow enables the rational selection and experimental realization of metal–organic frameworks combining data mining, machine-learning driven adsorption prediction, and structure generation, with experimental synthesis and validation within a closed-loop discovery pipeline. Analysis of existing and newly generated MOFs reveals the structure–property relationships governing low-pressure methane adsorption, identifying an optimal pore size and shape, framework densities, linker functionalities, and framework topologies that maximize dispersive C–H/π and van der Waals interactions. Beyond the specific materials identified herein, the results establish this workflow as a scalable and extensible platform for accelerated MOF discovery, with clear routes toward further optimization and automation while demonstrating practical applicability beyond purely theoretical exploration of hypothetical materials.

We report an end-to-end computational–experimental workflow for the discovery of metal–organic frameworks (MOFs), demonstrated by the computational design and synthesis of two novel Zn-based frameworks, UCHI-1 and UCHI-2, exhibiting enhanced methane uptake and selectivity at low pressure under ambient conditions (298 K, 1 bar). The workflow enables the rational selection and experimental realization of metal-organic frameworks combining data mining, machine-learning driven adsorption prediction, and structure generation, with experimental synthesis and validation within a closed-loop discovery pipeline. Analysis of existing and newly generated MOFs reveals the structure–property relationships governing low-pressure methane adsorption, identifying an optimal pore size and shape, framework densities, linker functionalities, and framework topologies that maximize dispersive C–H/π and Van der Waals interactions. Beyond the specific materials identified herein, the results establish this workflow as a scalable and extensible platform for accelerated MOF discovery, with clear routes toward further optimization and automation while demonstrating practical applicability beyond purely theoretical exploration of hypothetical materials.

We report an end-to-end computational–experimental workflow for the discovery of metal–organic frameworks (MOFs), demonstrated by the computational design and synthesis of two novel Zn-based frameworks, UCHI-1 and UCHI-2, exhibiting enhanced methane uptake and selectivity at low pressure under ambient conditions (298 K, 1 bar). The workflow enables the rational selection and experimental realization of metal-organic frameworks combining data mining, machine-learning driven adsorption prediction, and structure generation, with experimental synthesis and validation within a closed-loop discovery pipeline. Analysis of existing and newly generated MOFs reveals the structure–property relationships governing low-pressure methane adsorption, identifying an optimal pore size and shape, framework densities, linker functionalities, and framework topologies that maximize dispersive C–H/π and Van der Waals interactions. Beyond the specific materials identified herein, the results establish this workflow as a scalable and extensible platform for accelerated MOF discovery, with clear routes toward further optimization and automation while demonstrating practical applicability beyond purely theoretical exploration of hypothetical materials.

Understanding water sorption in metal‐organic frameworks (MOFs) is essential for advancing atmospheric water harvesting (AWH). Yet, most studies rely on bulk measurements that mask intrinsic material properties and particle heterogeneity. Here, we systematically examine how defect chemistry, residual guest molecules, and metal substitution shape water uptake in MOF‐801 and MOF‐808 at the single‐crystal level. Using bulk characterization together with in situ single‐crystal Raman spectroscopy, digestion ¹ H NMR, computational modeling, and long‐term cycling experiments, we disentangled how substituting Zr with Hf and changing topology affect the sorption behavior. Single‐crystal measurements reveal substantial crystal‐to‐crystal variations in residual DMF, which directly reduce the accessible pore volume and alter adsorption isotherms—effects hidden in ensemble‐averaged data. In both MOFs, Zr‐based materials exhibit higher uptake due to defect‐induced porosity. Hf substitution lowers the intrinsic defect density and improves cycling stability, but also leads to stronger solvent coordination and reduced pore accessibility. This trade‐off is most pronounced in MOF‐808(Zr), which shows high uptake but collapses during cycling, whereas the Hf analogue remains structurally stable at reduced capacity. By resolving how defects, guest molecules, and metal identity interplay at the single‐crystal level, this work provides molecular design rules for balancing stability and performance in next‐generation AWH sorbents.

Fe₄S₄ clusters play essential roles in nature, classically in electron transport but increasingly in newly discovered reactivity or catalysis. These roles have spurred interest in developing synthetic Fe₄S₄ systems and while several molecular and material systems built from Fe₄S₄ clusters have been developed, comparatively few examples of synthetic Fe₄S₄ cluster-based catalysts exist. Herein, we present the use of an Fe₄S₄-based coordination polymer as a catalyst for the direct and selective electroreduction of CO₂ to CO. Computational studies suggest that the reaction proceeds through CO₂ binding to a reduced Fe₄S₄ cluster, followed by a series of protonation, reduction, and H₂O loss steps to yield a CO-bound cluster that can finally exchange with CO₂ to restart the catalytic cycle. CO bound clusters are predicted to be thermodynamically stable, suggesting that carbonyl species might be off-cycle intermediates. Mechanistic CV studies as well as in situ studies by IR spectroscopy provide evidence for carbonyl-ligated clusters, supporting these compounds as unusual examples of small molecule binding to Fe₄S₄ clusters. This work establishes Fe₄S₄ cluster-based coordination polymers as direct electrocatalysts for CO₂ reduction and provides mechanistic insights into how these species mediate catalytic conversions of small molecules.

Fe₄S₄ clusters play essential roles in nature, classically in electron transport but increasingly in newly discovered reactivity or catalysis. These roles have spurred interest in developing synthetic Fe4S4 systems and while several molecular and material systems based on Fe₄S₄ clusters have been developed, comparatively few examples of synthetic Fe₄S₄ cluster-based catalysts exist. Herein, we present the use of an Fe₄S₄-based coordination polymer as a catalyst for the direct and selective electroreduction of CO2 to CO. Computational studies suggest that the reaction proceeds through CO2 binding to a reduced Fe4S4 cluster, followed by a series of protonation, reduction, and H2O loss steps to yield a CO-bound cluster that can finally exchange with CO2 to restart the catalytic cycle. CO bound clusters are predicted to be thermodynamically stable, suggesting that carbonyl species might be off-cycle intermediates. Mechanistic CV studies as well as in situ studies by IR spectroscopy provide evidence for carbonyl-ligated clusters, supporting these compounds as unusual examples of small molecule binding to Fe4S4 clusters. This work establishes Fe4S4 cluster-based coordination polymers as direct electrocatalysts for CO2 reduction and provides mechanistic insights into how these clusters mediate catalytic conversions of small molecules.

Electrochemical hydrogenation (e-H) of organic substrates represents a key transformation for advancing industrial electrification and sustainable chemical manufacturing. Here, we represent e-H of acetone and pyridine by cobalt nanoparticles derived from a Co-based MOF. A novel two-dimensional cobalt metal–organic framework, Co-L0-NS, featuring a kgd-type layered topology with Co(II) paddlewheel nodes and polyaromatic linkers, has been synthe-sized and structurally characterized. Electrochemical reduction of Co-L0-NS induces controlled framework recon-struction, producing highly dispersed cobalt nanoparticles that efficiently catalyze the e-H of acetone to isopropanol and show moderate activity toward pyridine reduction to piperidine. In contrast, electrodeposition from aqueous Co²⁺ precursors forms larger, more crystalline metallic Co particles. Spectroscopic and electrochemical analyses, sup-ported by Tafel modeling, indicate a proton-coupled electron-transfer (PCET) mechanism with a rate-determining step exhibiting a Tafel slope of ~150 mV dec⁻¹. These findings highlight how structural features of the parent MOF—open Co sites, two-dimensional connectivity, and redox flexibility—govern nanoparticle formation and catalytic be-havior, providing design principles for MOF-derived cobalt electrocatalysts.

Metal-substituted Cr(iv) qubits studied via CASPT2/MC-PDFT reveal Ti(ii) as a qubit candidate. Considering geometrical deformations show changes in relative energy gaps between excited states, this can provide some inspiration for ligand design.

The discovery of novel molecular systems for quantum information processing remains a major challenge for advancing molecular qubit technology. In the realm of optically addressable systems, a previously synthesized and characterized Cr(IV) pseudo-tetrahedral complex, featuring four strongly donating o-tolyl ligands surrounding the chromium center, has demonstrated potential as a qubit candidate. This study proposes analogs of this complex through a metal substitution strategy, extending the investigation to new complexes. The new metal centers were selected from first-row and Group 6 transition metals. Multiconfigurational methods such as the complete active space followed by second-order perturbation theory and multiconfiguration pair-density functional theory were utilized to calculate energy gaps between electronic states with different spins and zero-field splitting (ZFS). The results corroborate previous experimental findings for the Cr complex. Additionally, this study identifies a previously unsynthesized Ti(II) compound as a promising candidate for molecular qubits. This finding highlights the role of computational multireference methods in the rational design of qubit systems.