Exploring the potential of iron-based metal-organic frameworks as peroxidase nanozymes for glucose detection with various secondary building units.

Finding materials in biosensing that balance enzyme-like reactivity, stability, and affordability is essential for the future. Because of their unique peroxidase properties, including variable pore size, surface area, and Lewis acid active sites, iron-based metal-organic frameworks (MOFs) have evolved as viable possibilities. In this study, we constructed a Fe-MOF and tested its peroxidase-like activity and responsiveness toward HO colorimetric techniques.

Synergistic Functionality of Dopants and Defects in Co-Phthalocyanine/B-CN Z-Scheme Photocatalysts for Promoting Photocatalytic CO Reduction Reactions.

The realization of solar-light-driven CO  reduction reactions (CO RR) is essential for the commercial development of renewable energy modules and the reduction of global CO emissions. Combining experimental measurements and theoretical calculations, to introduce boron dopants and nitrogen defects in graphitic carbon nitride (g-C N ), sodium borohydride is simply calcined with the mixture of g-C N (CN), followed by the introduction of ultrathin Co phthalocyanine through phosphate groups. By strengthening H-bonding interactions, the resultant CoPc/P-BNDCN nanocomposite showed excellent photocatalytic CO reduction activity, releasing 197.

Regulating the Coordination Environment of Single-Atom Catalysts Anchored on Thiophene Linked Porphyrin for an Efficient Nitrogen Reduction Reaction.

The electrochemical nitrogen reduction reaction (NRR) offers a promising strategy to resolve high energy consumption in the nitrogen industry. Recently, the regulation of the electronic structure of single-atom catalysts (SACs) by adjusting their coordination environment has emerged as a rather promising strategy to further enhance their electrocatalytic activity. Herein, we design novel SACs supported by thiophene-linked porphyrin (TM-N/TP and TM-NB/TP, where TM = Sc to Au) as potential NRR catalysts using density functional theory calculations.

Hydrogen-Bond-Donor-Directed Switching of Enantioselectivity in the Vinylogous Aldol-Cyclization Cascade Reaction of Prostereogenic 3-Alkylidene Oxindoles with Isatins and -Quinones.

In this study, we reported a hydrogen-bond-donor-directed enantiodivergent vinylogous aldol-cyclization cascade reaction of 3-alkylidene oxindoles with isatins and -quinones. Both enantiomers can be prepared by thiourea or squaramide cinchona alkaloid bifunctional organocatalysts with the same quinine scaffold. Kinetic study data provided the possible reaction mechanism for the vinylogous aldol-cyclization cascade reaction.

Mechanistic Insight into the Synergetic Interaction of Ammonia Borane and Water on ZIF-67-Derived Co@Porous Carbon for Controlled Generation of Dihydrogen.

Regarding dihydrogen as a clean and renewable energy source, ammonia borane (NHBH, AB) was considered as a chemical H-storage and H-delivery material due to its high storage capacity of dihydrogen (19.6 wt %) and stability at room temperature. To advance the development of efficient and recyclable catalysts for hydrolytic dehydrogenation of AB with parallel insight into the reaction mechanism, herein, ZIF-67-derived fcc-Co@porous carbon nano/microparticles (cZIF-67_nm/cZIF-67_μm) were explored to promote catalytic dehydrogenation of AB and generation of H.

Unraveling Catalytic Mechanisms for CO Oxidation on Boron-Doped Fullerene: A Computational Study.

By means of spin-polarized density functional theory (DFT) computations, we unravel the reaction mechanisms of catalytic CO oxidation on B-doped fullerene. It is shown that O species favors to be chemically adsorbed via side-on configuration at the hex-C-B site with an adsorption energy of -1.07 eV.

Synthesis, density functional theory (DFT) studies and urease inhibition activity of chiral benzimidazoles.

A variety of benzimidazole by the heterocyclization of orthophenylenediamine were synthesized in 69-86% yields. The synthesized compounds and were characterized and further investigated as jack bean urease inhibitors. Density functional theory (DFT) studies were performed utilizing the basis set B3LYP/6-31G (d, p) to acquire perception into their structural properties.

Computational Study on the Mechanisms and Rate Constants for the O(P,D) + OCS Reactions.

The mechanisms and kinetics of O(P,D) + OCS(XΣ) reactions have been studied by the high-level G2M(CC2) and CCSD(T)/6-311+G(3df)//B3LYP/6-311+G(3df) methods in conjunction with the transition-state theory and variational Rice-Ramsperger-Kassel-Marcus theory calculations. The result shows that the triplet surface proceeds directly by abstraction and substitution channels to produce SO(P) + CO(XΣ) and S(P) + CO(X Σ) by passing the barriers of 7.6 and 9.

Single Pt atom supported on penta-graphene as an efficient catalyst for CO oxidation.

Single-atom catalysts (SACs) have gained special attention due to their unique performances in CO oxidation. Herein, a single Pt atom supported on penta-graphene (Pt/PG) was explored as a SAC towards CO oxidation by applying spin-polarized first-principles calculations. The possible mechanisms for CO oxidation by O on Pt/PG, including two traditional mechanisms, Eley-Rideal (ER) and Langmuir-Hinshelwood (LH), and a new tri-molecular Eley-Rideal (TER) mechanism, are illustrated.

A simple approach to achieve a metastable metal oxide derived from carbonized metal-organic gels.

A strategy for fabricating zirconium oxide doped nanoporous carbons derived from metal-organic gels (MOGs) is reported. For the first time, the achievement of metastable ZrO2-NPCs is demonstrated. The direct pyrolysis of MOGs provided new perspective in developing metal oxide-doped NPCs and circumvented the shortcomings of existing methods in synthesizing metastable ZrO2 doped NPCs.

Catalytic CO oxidation on B-doped and BN co-doped penta-graphene: a computational study.

The catalytic reaction of carbon monoxide oxidation on boron-doped and boron-nitrogen co-doped penta-graphene materials has been systematically studied by utilizing spin-polarized density functional theory (DFT) calculations. Various pathways including the Eley-Rideal (ER), Langmuir-Hinshelwood (LH), and tri-molecular Eley-Rideal (TER) mechanisms were considered in which the TER mechanism is a newly proposed reaction mechanism for CO oxidation. According to the calculation results, the ER, LH and TER mechanisms of CO oxidation can occur and compete with each other because of the related small overall reaction energy barriers (0.

Monitoring the Effect of Different Metal Centers in Metal-Organic Frameworks and Their Adsorption of Aromatic Molecules using Experimental and Simulation Studies.

In this study, the adsorption behavior of different metal centers in analogous M-1,4-NDC frameworks (1,4-NDC=1,4-naphthalenedicarboxylate) towards guest molecules through simulation studies and experimental studies is reported. Simulation studies showed that the adsorption behavior of analogous M-1,4-NDC is affected by the atomic radius of the metal center, which was found to be in agreement with the experimental studies.

Nitrogen-doped C as a robust catalyst for CO oxidation.

The O activation and CO oxidation on nitrogen-doped C N fullerene are investigated using first-principles calculations. The calculations indicate that the C N fullerene is able to activate O molecules resulting in the formation of superoxide species ( O2-) both kinetically and thermodynamically. The active superoxide can further react with CO to form CO via the Eley-Rideal mechanism by passing a stepwise reaction barrier of only 0.

Nitrogen-doped porous carbon material derived from metal-organic gel for small biomolecular sensing.

A simple preparation method of N-doped PCM via direct carbonization of nitrogen containing metal-organic gel was demonstrated. The resultant N-PCM, with high surface area, mesoporosity, and high UV absorption ability, was used as a matrix to assist small-biomolecule sensing in laser desorption/ionization mass spectrometry.

Investigation of the self-assembly of CS and PCL copolymers with different molecular weights in water solution by coarse-grained molecular dynamics simulation.

Coarse-grained molecular dynamics (CGMD) simulation was employed to investigate how stable chondroitin sulfate-graft-polycaprolactone (CS-PCL, CP) copolymers self-assemble into micelles in an aqueous environment. Three types of CP containing low (2.4%), medium (6.

Nitrogen-doped carbon nanotube as a potential metal-free catalyst for CO oxidation.

We elucidate the possibility of nitrogen-doped carbon nanotube as a robust catalyst for CO oxidation. We have performed first-principles calculations considering the spin-polarization effect to demonstrate the reaction of CO oxidation catalyzed by the nitrogen-doped carbon nanotube. The calculations show that O2 species can be partially reduced with charge transfer from the nitrogen-doped carbon nanotube and directly chemisorbed on the C-N sites of the nitrogen-doped carbon nanotube.

The CO oxidation mechanism on the W(111) surface and the W helical nanowire investigated by the density functional theory calculation.

Two CO oxidation reactions (CO + O2 → CO2 + O and CO + O → CO2) were considered in the Eley-Rideal (ER) reaction mechanism. These oxidation processes on the W(111) surface and the W helical nanowire were investigated by the density functional theory (DFT) calculation. The stable adsorption sites of O2 and O as well as their adsorption energies were obtained first.

To Transfer or Not to Transfer? Development of a Dinitrosyl Iron Complex as a Nitroxyl Donor for the Nitroxylation of an Fe(III) -Porphyrin Center.

A positive myocardial inotropic effect achieved using HNO/NO(-) , compared with NO⋅, triggered attempts to explore novel nitroxyl donors for use in clinical applications in vascular and myocardial pharmacology. To develop M-NO complexes for nitroxyl chemistry and biology, modulation of direct nitroxyl-transfer reactivity of dinitrosyl iron complexes (DNICs) is investigated in this study using a Fe(III) -porphyrin complex and proteins as a specific probe. Stable dinuclear {Fe(NO)2 }(9) DNIC [Fe(μ-(Me) Pyr)(NO)2 ]2 was discovered as a potent nitroxyl donor for nitroxylation of Fe(III) -heme centers through an associative mechanism.

Promoting ethylene epoxidation on gold nanoclusters: self and CO induced O2 activation.

We have investigated the epoxidation of ethylene heterogeneously catalyzed by small gold nanoclusters based on density functional theory calculations. A promising trimolecular Langmuir-Hinshelwood mechanism via co-adsorbed ethylene- and CO-assisted reaction is addressed which provides significant insights into the fundamental catalytic mechanism for ethylene oxidation on small Au nanoclusters. O2 activation is found to be a key step for accelerating ethylene oxidation.

Adsorption and Reaction of C₂H₄ and O₂ on a Nanosized Gold Cluster: A Computational Study.

We have investigated the adsorption and reaction mechanisms of C2H4 and O2 catalyzed by a Au38 nanoparticle based on periodic density-functional theory (DFT) calculations. The configurations of the adsorption of C2H4/Au38, O2/Au38, and O/Au38 as well as the coadsorption of C2H4-O2/Au38 were predicted. The calculation results show that C2H4, O2, and O are preferably bound at top (T), bridge (B), and hexagonal (h) sites with adsorption energies of -0.

Hydrogen generation by the reaction of H2O with Al2O3-based materials: a computational analysis.

The mechanisms for H2O adsorption on γ-Al2O3(110) surface were investigated to illustrate the influence of oxide modifiers on the hydrogen generation reaction. Periodic density functional theory (DFT) calculations with the projected augmented wave (PAW) approach were carried out to study the adsorption of H2O, OH, O and H species, as well as the reaction mechanisms of H2O splitting and H2 generation. Their corresponding structures and adsorption energies are also reported.

Computational study of the kinetics and mechanisms for the HCO + O3 reaction.

The mechanisms of radical-molecule reactions between HCO (formyl radical) and O3 (ozone) have been investigated by using BH&HLYP and QCISD methods with the 6-311++G(3df,2p) basis set. The energetics have been refined with CCSD(T) and QCISD(T) theoretical approaches with the same basis set based on the geometries calculated at the QCISD method. The intermediates of hydrogen-bonded complexes and the critical transition states are also examined with the multireference methods.

A density functional theory study on the structure stability of silica nanoclusters.

The studies of silica nanoclusters are of substantial interest for large potential in applications as diverse as photonics/optics, microelectronics and catalysis. In this study, we used the basing-hopping method with Buckingham potential to get the stable structures of silica nanoclusters ((SiO2)(n) = 1-13). The global minimum geometry of silica nanoclusters were determined by density functional theory calculation.

The dynamics behavior of Rh nanoclusters on boron nitride sheet.

The configurations and corresponding adsorption energies of Rh(n) (n = 4-13) nanoclusters on the boron nitride sheet are investigated by density functional theory (DFT). We use the force-matching method (FMM) to modify parameters of Morse and Tersoff potential functions. To elucidate the dynamical behaviors of Rh nanoclusters on the boron nitride sheet, molecular dynamics (MD) is applied with modified Morse potential function parameter.