A polymeric hydrogel electrocatalyst for direct water oxidation

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Feb. 13, 2023

Metal-free electrocatalysts represent a main branch of active materials for oxygen evolution reaction (OER), but they excessively rely on functionalized conjugated carbon materials, which substantially restricts the screening potential efficient carbonaceous electrocatalysts. Herein, we demonstrate that mesostructured polyacrylate hydrogel can afford an unexpected and exceptional OER activity - par with benchmark IrO2 catalyst in alkaline electrolyte, together high durability good adaptability various pH environments. Combined theoretical electrokinetic studies reveal positively charged atoms within carboxylate units are intrinsically toward OER, spectroscopic operando characterizations also identify fingerprint superoxide intermediate generated polymeric backbone. This work expands scope metal-free by providing new class huge extension potentials.

Language: Английский

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Rational In Silico Design of Molecularly Imprinted Polymers: Current Challenges and Future Potential

International Journal of Molecular Sciences, Journal Year: 2023, Volume and Issue: 24(7), P. 6785 - 6785

Published: April 5, 2023

The rational design of molecularly imprinted polymers has evolved along with state-of-the-art experimental imprinting strategies taking advantage sophisticated computational tools. In silico methods enable the screening and simulation innovative polymerization components conditions superseding conventional formulations. combined use quantum mechanics, molecular dynamics allows for macromolecular modelling to study systematic translation from pre- post-polymerization stage. However, predictive high-performance computing advance MIP development are neither fully explored nor practiced comprehensively on a routine basis date. this review, we focus different steps process discuss appropriate that may assist in optimizing associated strategies. We potential, challenges, limitations approaches including ML/AI present perspectives guide next-generation accelerating discovery templated materials.

Language: Английский

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Hybrid Cluster-Continuum Method for Single-Ion Solvation Free Energy in Acetonitrile Solvent

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: 128(31), P. 6440 - 6449

Published: July 25, 2024

A new hybrid discrete-continuum approach named the cluster-continuum static approximation (CCSA) has been proposed for acetonitrile solvent. The continuum part uses conductor-like polarizable model electrostatic and a surface area-dependent term nonelectrostatic solvation. CCSA includes only one explicit solvent molecule damping function, which makes method reduce to pure solvation in case of weaker potential mean force solute-solvent interaction. performance was tested 22 anions cations, including challenge species that cannot be adequately described by comparison done with widely used density (SMD) model. For anions, reduces same as SMD model, standard deviation signed error (SD-MSE) 2.7 kcal mol

Language: Английский

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Conformational energies of biomolecules in solution: Extending the MPCONF196 benchmark with explicit water molecules

Journal of Computational Chemistry, Journal Year: 2023, Volume and Issue: 45(7), P. 419 - 429

Published: Nov. 19, 2023

Abstract A prerequisite for the computational prediction of molecular properties like conformational energies biomolecules is a reliable, robust, and computationally affordable method usually selected according to its performance relevant benchmark sets. However, most these sets comprise molecules in gas phase do not cover interactions with solvent, even though typically occur aqueous solution. To address this issue, we introduce explicit water solvated version gas‐phase set containing 196 conformers 13 peptides other macrocycles, namely MPCONF196 [J. Řezáč et al., JCTC 2018 , 14 1254–1266], provide very accurate PNO‐LCCSD(T)‐F12b/AVQZ' reference values. The novel solvMPCONF196 features two additional challenges beyond description phase: conformer–water water–water interactions. overall best performing double hybrid revDSDPBEP86‐D4/def2‐QZVPP yielding almost coupled cluster quality. Furthermore, some (meta‐)GGAs functionals B97M‐V B97M‐D large basis reproduce an MAD below 1 kcal mol . If more efficient methods are required, composite DFT‐method rSCAN‐3c (MAD 1.2 mol) good alternative, when polypeptides or macrocycles than 500–1000 atoms focus, semi‐empirical GFN2‐xTB MMFF94 force field (for systems) recommended.

Language: Английский

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N-Oxide Insertion into LDA Dimeric Aggregates for Azomethine Ylide Formation: Explicit Solvation in Quantum Mechanical Treatment of Polarized Intermediates

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: 90(10), P. 3673 - 3683

Published: March 1, 2025

The physical model used to compute natural phenomena is crucial for accurate structural and mechanism elucidation. Specifically, we examine the mechanistic consequences of an explicit LDA dimer, THF, N-oxide aggregate formation at rate-limiting step two competing reaction pathways involving nitrogen–oxygen dissociation alpha-hydrogen deprotonation azomethine ylide formation. We free energies activation using M06-2x, B3LYP, HCTH407 functionals second-order Møller–Plesset perturbation theory with Dunning's correlation consistent basis sets cc-pV[D,T]Z, corrected entropy by Whitesides' volume theory. Our discrete-continuum approach uses Tomasi's polarizable continuum complement quantum system incorporating bulk solvent effects. Building off aggregation work developed Collum coworkers, demonstrate that inclusion can have a profound impact on predicted energy barriers alignment experimental product distributions. In polarized system, use more sophisticated balanced underscores importance correct pattern aggregation. results identify unique incorporates N-oxide, formation, which suggests third dimension John Pople diagram enhance accuracy through sophistication.

Language: Английский

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Protonated Porphyrins: Bifunctional Catalysts for the Metal‐Free Synthesis of N‐Alkyl‐Oxazolidinones

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 29(1)

Published: Oct. 4, 2022

The protonation of commercially available porphyrin ligands yields a class bifunctional catalysts able to promote the synthesis N-alkyl oxazolidinones by CO

Language: Английский

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Guiding Principles for the Rational Design of Hybrid Materials: Use of DFT Methodology for Evaluating Non‐Covalent Interactions in a Uranyl Tetrahalide Model System

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(33)

Published: May 13, 2023

Together with the synthesis and experimental characterization of 14 hybrid materials containing [UO

Language: Английский

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Remote Functionalization by Pd-Catalyzed Isomerization of Alkynyl Alcohols

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(27), P. 18606 - 18615

Published: June 28, 2024

In recent years, progress has been made in the development of catalytic methods that allow remote functionalizations based on alkene isomerization. contrast, protocols alkyne isomerization are comparatively rare. Herein, we report a general Pd-catalyzed long-range alkynyl alcohols. Starting from aryl-, heteroaryl-, or alkyl-substituted precursors, optimized system provides access preferentially to thermodynamically more stable α,β-unsaturated aldehydes and is compatible with potentially sensitive functional groups. We showed migration both π-components carbon–carbon triple bond can be sustained over several methylene units. Computational investigations served shed light key elementary steps responsible for reactivity selectivity. These include an unorthodox phosphine-assisted deprotonation rather than conventional β-hydride elimination final tautomerization event.

Language: Английский

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Revealing the Hidden Complexity and Reactivity of Palladacyclic Precatalysts: The P(o-tolyl)₃ Ligand Enables a Cocktail of Active Species Utilizing the Pd(II)/Pd(IV) and Pd(0)/Pd(II) Pathways for Efficient Catalysis

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(17), P. 12769 - 12782

Published: Aug. 9, 2024

The ligand, P(o-tolyl)3, is ubiquitous in applied synthetic chemistry and catalysis, particularly Pd-catalyzed processes, which typically include Pd(OAc)2 (most commonly used as Pd3(OAc)6) a precatalyst. Herrmann–Beller palladacycle [Pd(C^P)(μ2-OAc)]2 (where C^P = monocyclopalladated P(o-tolyl)3) easily formed from reaction of with P(o-tolyl)3. mechanisms by this precatalyst system operates are inherently complex, studies previously implicating Pd nanoparticles (PdNPs) reservoirs for active Pd(0) species arylative cross-coupling reactions. In study, we reveal the fascinating, nontrivial behavior palladacyclic group. First, presence hydroxide base, readily converted into an activated form, [Pd(C^P)(μ2-OH)]2, serves conduit activation to catalytically relevant species. Second, palladacyclization imparts unique stability catalytic under conditions, bringing play Pd(II)/Pd(IV) mechanism. For benchmark Suzuki–Miyaura (SMCC) reaction, there shift mononuclear pathway PdNP-controlled during reaction. [Pd(C^P)(μ2-OH)]2 has been studied using arylphosphine-stabilized boronic acid low-temperature NMR spectroscopic analysis, sheds light on preactivation step, water and/or being critical formation Pd(II) situ monitoring demonstrated that sensitivity structure arylboron pinacol. This work, taken together, highlights mechanistic complexity accompanying use systems. It builds recent findings involving related Pd(OAc)2/PPh3 systems form higher order Pdn clusters PdNPs conditions. Thus, generally, one needs be cautious assumption Pd(OAc)2/tertiary phosphine mixtures cleanly deliver "Pd(0)Ln" any assessment individual ligands may need case-by-case basis.

Language: Английский

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On the Stability Constants of Metal-Nitrate Complexes in Aqueous Solutions

Physical Chemistry Chemical Physics, Journal Year: 2025, Volume and Issue: 27(18), P. 9350 - 9368

Published: Jan. 1, 2025

Stability constants of simple reactions involving addition the NO3- ion to hydrated metal complexes, [M(H2O)x]n+ are calculated with a computational workflow developed using cloud computing resources. The performs conformational searches for complexes at both low and high levels theories in conjunction continuum solvation model (CSM). low-level theory is mainly used initial searches, which complemented high-level density functional CSM framework determine coordination chemistry relevant stability constant calculations. In this regard, lowest energy conformations found obtain reaction free energies one where M represents Fe(II), Fe(III), Sr(II), Ce(III), Ce(IV), U(VI), respectively. Structural analysis hundreds optimized geometries reveals that coordinates Fe(II) Fe(III) either monodentate or bidentate manner. Interestingly, lowest-energy metal-nitrate exhibit number 6 while seven-coordinated approximately 2 kcal mol-1 higher energy. Notably, configuration more stable than six-coordinated (monodentate bidentate) by few thermal units. contrast, U(VI) ions predominantly coordinate manner, exhibiting typical numbers 7, 9, 5, accordingly linear approaches account systematic errors good agreements obtained between available experimental data.

Language: Английский

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