Homoleptic magnesium and calcium complexes supported by constrained reduced Schiff base ligand for lactide polymerisation: DFT analysis of lactide/ligand interactions.

A homoleptic calcium complex supported by a constrained reduced Schiff base ligand was synthesised and found to be highly active for the ring-opening polymerisation (ROP) of 100 equiv. lactide within 2 min at room temperature. However, the magnesium analogue has significantly lower reactivity.

Redox-Conjugated Co-Phthalocyanine-Phenazine Polymer as a Robust Catalyst for Efficient Electrochemical CO Conversion.

This work reports the synthesis and electropolymerization of 4-aminophenoxy-substituted Co-phthalocyanine to prepare a phenazine (PNZ)-bridged Co-phthalocyanine polymer as a durable catalyst for heterogeneous electrochemical CO reduction (ECOR). At -1.19 V versus normal hydrogen electrode, the ECOR under catalysis of the target polymer effectively produces CO with 94% faradaic efficiency (FE), CO partial current density of 5.

Ultrafast CO Capture from Dilute Streams in Quasi-Equipotential Pores of Metal-Organic Frameworks.

Solid sorbents capable of capturing CO at particularly low concentrations with rapid kinetics are crucial for effective CO capture. Here, we report ZnDTZ, a metal-organic framework (MOF) designed with an optimized pore size and functionalized pore surfaces tailored for CO adsorption. ZnDTZ MOF exhibits exceptional CO capture performance, achieving an uptake of 1.

Simultaneous Electrochemical Upgrading of Biomass and CO Utilization Using Fe/Ni-Derived Carbon Nanotubes Derived from CO.

Fossil fuel consumption has caused petroleum shortages and increased carbon emissions; thus, utilizing renewable resources in biorefineries for biomass-derived chemical synthesis is promising. Among them, 2,5-furandicarboxylic acid (FDCA) is a key alternative to terephthalic acid (PTA) for sustainable polyester production. In this work, we demonstrate an efficient approach for the simultaneous production of FDCA while utilizing carbon dioxide (CO₂) via an electrochemical approach.

Bimetallic constrained aluminum alkoxide complexes for ring-opening polymerization of cyclic esters: activity enhancement cationic activation.

Dinuclear aluminum complexes bearing a constrained 'indanimine' ligand based on a short hydrazine bridge were synthesized. Single-crystal X-ray crystallography reveals bimetallic penta-coordinated aluminum centers having a distorted trigonal bipyramidal geometry. A short Al-Al distance of 4.

Engineering Lewis-Acid Defects on ZnO Quantum Dots by Trace Transition-Metal Single Atoms for High Glycerol-to-Glycerol Carbonate Conversion.

Efficient conversion of biomass wastes into valuable chemicals has been regarded as a sustainable approach for green and circular economy. Herein, a highly efficient catalytic conversion of glycerol (Gly) into glycerol carbonate (GlyC) by carbonylation with the commercially available urea is presented using low-cost transition metal single atoms supported on zinc oxide quantum dots (M-ZnO QDs) as a catalyst without using any solvent. A facile one-step wet chemical synthesis allows various types of metal single atoms to simultaneously dope and introduce Lewis-acid defects in the ZnO QD structure.

Rational Design of Fe Single Sites Supported on Hierarchical Zeolites Atomic Layer Deposition for Few-Walled Carbon Nanotube Production.

Metal single-site catalysts have recently played an essential role in catalysis due to their enhanced activity, selectivity, and precise reaction control compared to those of conventional metal cluster catalysts. However, the rational design and catalytic application of metal single-site catalysts are still in the early stages of development. In this contribution, we report the rational design of Fe single sites incorporated in a hierarchical ZSM-5 atomic layer deposition (ALD).

Unraveling the Electrocatalytic Activity in HMF Oxidation to FDCA by Fine-Tuning the Degree of NiOOH Phase Over Ni Nanoparticles Supported on Graphene Oxide.

The development of an efficient electrocatalyst for HMF oxidation to FDCA has been in the early stages. Herein, the NiNPs/GO-Ni-foam is fabricated as an electrocatalyst for FDCA production. However, the electrocatalytic performance of the untreated NiNPs/GO-Ni-foam is observed with moderate Faradaic efficiency (FE) (73.

General Pyrolysis for High-Loading Transition Metal Single Atoms on 2D-Nitro-Oxygeneous Carbon as Efficient ORR Electrocatalysts.

Single-atom catalysts (SACs) possess the potential to involve the merits of both homogeneous and heterogeneous catalysts altogether and thus have gained considerable attention. However, the large-scale synthesis of SACs with rich isolate-metal sites by simple and low-cost strategies has remained challenging. In this work, we report a facile one-step pyrolysis that automatically produces SACs with high metal loading (5.

Photochemical engineering unsaturated Pt islands on supported Pd nanocrystals for a robust pH-universal hydrogen evolution reaction.

The rational design of heterostructured nanocrystals (HNCs) is of great significance for developing highly efficient hydrogen evolution reaction (HER) electrocatalysts. However, a significant challenge still lies in realizing the controllable synthesis of desired HNCs directly onto a support and exploring their structure-activity-dependent HER performance. Herein, we reported various controllable Pd@Pt core-shell HNCs with optimal hybrid structures a photochemical deposition strategy.

Efficient exploration of transition-metal decorated MXene for carbon monoxide sensing using integrated active learning and density functional theory.

The urgent demand for chemical safety necessitates the real-time detection of carbon monoxide (CO), a highly toxic gas. MXene, a 2D material, has shown potential for gas sensing applications (, NH, NO, SO, CO) due to its high surface accessibility, electrical conductivity, stability, and flexibility in surface functionalization. However, the pristine MXene generally exhibits poor interaction with CO; still, transition metal decoration can strengthen the interaction between CO and MXene.

Enhanced Electrocatalytic CO Reduction Reactivity of S- and N-Doped Fe-Embedded Graphene.

In this work, we studied the reaction mechanisms for CO reduction reaction (CRR) on the iron-doped graphene and its coordinating sulfur (S) and nitrogen (N) variants, FeN S (n=1-4), using density functional theory calculations. Our results revealed that the electronic property and catalytic reactivity of the surfaces can be tuned by varying the N and S atoms ratio. The CRR activities of the mixed surfaces, FeN S , FeN S , and FeN S , were better than FeN and FeS , where the absolute value of the limiting potential of the mixed surface decreased by 0.

Unraveling the Adsorption Behavior of Thymol on Carbon and Silica Nanospheres for Prolonged Antibacterial Activity: Experimental and DFT Studies.

Functionalization of thymol (Thy) on nanocarriers is a key step in achieving prolonged antimicrobial activity. This requires nanomaterials with uniform particle diameters and suitable thymol sorption. Herein, hollow carbon (HC) and SiO-carbon core-shell (SiO@C) were investigated due to their diverse morphologies and ease of surface modification.

Impact of exposed crystal facets on oxygen reduction reaction activity in zeolitic imidazole frameworks.

ZIF-67 is a representative type of metal-organic framework (MOF) developed for the oxygen reduction reaction (ORR) owing to its robust structure in alkaline electrolytes and the presence of the redox-active Co species in the structure. In this work, the improvement of the ORR electrolytic performance of ZIF-67 in its pure phase by optimization of its crystal morphology and crystal facets has been presented. ZIF-67 nanocubes exhibit higher ORR activity than their bulk crystals.

Data-Driven Discovery of Graphene-Based Dual-Atom Catalysts for Hydrogen Evolution Reaction with Graph Neural Network and DFT Calculations.

The flexible tuning ability of dual-atom catalysts (DACs) makes them an ideal system for a wide range of electrochemical applications. However, the large design space of DACs and the complexity in the binding motif of electrochemical intermediates hinder the efficient determination of DAC combinations for desirable catalytic properties. A crystal graph convolutional neural network (CGCNN) was adopted for DACs to accelerate the high-throughput screening of hydrogen evolution reaction (HER) catalysts.

New Folding 2D-Layered Nitro-Oxygenated Carbon Containing Ultra High-Loading Copper Single Atoms.

The discoveries of 2D nanomaterials have made huge impacts on the scientific community. Their unique properties unlock new technologies and bring significant advances to diverse applications. Herein, an unprecedented 2D-stacked material consisting of copper (Cu) on nitro-oxygenated carbon is disclosed.

Metal-organic framework MIL-100(Fe) as a promising sensor for COVID-19 biomarkers detection.

The development of fast and non-invasive techniques to detect SARS-CoV-2 virus at the early stage of the infection would be highly desirable to control the COVID-19 outbreak. Metal-organic frameworks (MOFs) are porous materials with uniform porous structures and tunable pore surfaces, which would be essential for the selective sensing of the specific COVID-19 biomarkers. However, the use of MOFs materials to detect COVID-19 biomarkers has not been demonstrated so far.

Understanding the interaction between transition metal doping and ligand atoms of ZnS and ZnO monolayers to promote the CO reduction reaction.

Single-atom catalysts (SACs) obtained by doping transition metal (TM) atoms into stable monolayers are a promising way to improve the CO reduction reaction (CRR) performance. In this work, we theoretically investigated the effect of ligand atoms around the doped TM (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) in ZnO and ZnS for promoting the CRR performance. We found that the ligand atoms around the TM can influence its oxidation state and the electronic properties of the SACs, thus affecting their CRR activity.

Red to orange thermally activated delayed fluorescence polymers based on 2-(4-(diphenylamino)-phenyl)-9-thioxanthen-9-one-10,10-dioxide for efficient solution-processed OLEDs.

Most highly efficient thermally activated delayed fluorescence (TADF)-based organic light-emitting diodes (OLEDs) are multi-layer devices fabricated by thermal vacuum evaporation techniques, which are unfavorable for real applications. However, there are only a few reported examples of efficient solution-processed TADF OLEDs, in particular TADF polymer OLEDs. Herein, a series of solution-processable TADF conjugated polymers (PCTXO/PCTXO-F ( = 25, 50 and 75)) were designed and synthesized by copolymerization of 2-(4-(diphenylamino)-phenyl)-9-thioxanthen-9-one-10,10-dioxide (TXO-TPA) as a red/orange emissive TADF unit, 9,9'-((fluorene-9,9-diyl)-bis(octane-8,1-diyl))-bis(3,6-di--butylcarbazole) as host/hole-transporting unit and 2,7--(heptadecan-9-yl)carbazole as a conjugated linker and solubilizing group.

The improvement in hole-transporting and electroluminescent properties of diketopyrrolopyrrole pigment by grafting with carbazole dendrons.

Diketopyrrolopyrrole (DPP) pigments are essential and have been intensively exploited as building-blocks for the synthesis of organic semiconducting polymers and small molecules; however, DPP derivatives as emissive materials for electroluminescent (EL) devices have rarely been explored. In this work, a series of new DPP derivatives grafted with carbazole dendrons in a non-conjugated fashion using an amide linkage was designed to improve the performance of DPP in EL devices. Three DPP derivatives (G0DPP, G1DPP and G2DPP) bearing di(-chlorophenyl)-DPP (Pigment Red 254) as the core substituted with a hexyl chain, -hexyl carbazole and -hexyl-'-9,3':6',''-tercarbazole, respectively, were synthesized to afford improved hole-transporting properties without affecting the photophysical and electronic properties of the DPP core.

Adsorption and dehydration of ethanol on isomorphously B, Al, and Ga substituted H-ZSM-5 zeolite: an embedded ONIOM study.

Dehydration reactions are important in the petroleum and petrochemical industries, especially for the feedstock production. In this work, the catalytic activity of zeolites with different acidities for the dehydration of ethanol to ethylene and diethylether is investigated by density functional calculations on cluster models of three isomorphous B, Al, and Ga substituted H-ZSM-5 zeolites. Both unimolecular and bimolecular mechanisms are investigated.

Ti-Decorated B/N-doped graphene as a high-capacity hydrogen storage material: a DFT study.

The adsorption properties of the hydrogen atom on our newly designed materials were investigated using density functional theory (DFT) calculations, focusing on the role of dopants in modulating the binding properties of the metal. We proposed decorating Ti on pristine, B- and N-doped graphene surfaces for preparing a large-capacity hydrogen-storage device. Computational results indicate that the doping of B on graphene enhances the interaction between the metal cluster and the supporting substrate with a very strong binding energy of -6.

Highly Active Chromium Complexes Supported by Constrained Schiff-Base Ligands for Cycloaddition of Carbon Dioxide to Epoxides.

Novel constrained Schiff-base ligands (inden) were developed based on the well-known salen ligands. Chromium complexes supported by the constrained inden ligands were successfully synthesized and used as catalysts for the synthesis of cyclic carbonates from epoxides and carbon dioxide (CO). The catalyst having -butyl (Bu) groups as substituents in combination with tetrabutylammonium bromide (TBAB) as a cocatalyst exhibited very high catalytic activity with a turnover frequency of up to 14800 h for the conversion of CO and propylene oxide into propylene carbonate exclusively at 100 °C and 300 psi of CO under solvent-free conditions.

Effect of Water Microsolvation on the Excited-State Proton Transfer of 3-Hydroxyflavone Enclosed in γ-Cyclodextrin.

The effect of microsolvation on excited-state proton transfer (ESPT) reaction of 3-hydroxyflavone (3HF) and its inclusion complex with γ-cyclodextrin (γ-CD) was studied using computational approaches. From molecular dynamics simulations, two possible inclusion complexes formed by the chromone ring (C-ring, Form I) and the phenyl ring (P-ring, Form II) of 3HF insertion to γ-CD were observed. Form II is likely more stable because of lower fluctuation of 3HF inside the hydrophobic cavity and lower water accessibility to the encapsulated 3HF.

A Simple and Strong Electron-Deficient 5,6-Dicyano[2,1,3]benzothiadiazole-Cored Donor-Acceptor-Donor Compound for Efficient Near Infrared Thermally Activated Delayed Fluorescence.

Despite the success of thermally activated delayed fluorescent (TADF) materials in steering the next generation of organic light-emitting diodes (OLEDs), effective near infrared (NIR) TADF emitters are still very rare. Here, we present a simple and extremely high electron-deficient compound, 5,6-dicyano[2,1,3]benzothiadiazole (CNBz), as a strong electron-accepting unit to develop a sufficiently strong donor-acceptor (D-A) interaction for NIR emission. End-capping with the electron-donating triphenylamine (TPA) unit created an effective D-A-D type system, giving rise to an efficient NIR TADF emissive molecule (λ =750 nm) with a very small ΔE of 0.