Hydride-Induced Reconstruction of Pd Electrode Surfaces: A Combined Computational and Experimental Study.

Designing electrocatalysts with optimal activity and selectivity relies on a thorough understanding of the surface structure under reaction conditions. In this study, experimental and computational approaches are combined to elucidate reconstruction processes on low-index Pd surfaces during H-insertion following proton electroreduction. While electrochemical scanning tunneling microscopy clearly reveals pronounced surface roughening and morphological changes on Pd(111), Pd(110), and Pd(100) surfaces during cyclic voltammetry, a complementary analysis using inductively coupled plasma mass spectrometry excludes Pd dissolution as the primary cause of the observed restructuring.

Crystal engineering of a new platform of hybrid ultramicroporous materials and their CH/CO separation properties.

Hybrid ultramicroporous materials (HUMs) comprised of combinations of organic and inorganic linker ligands are a leading class of physisorbents for trace separations involving C1, C2 and C3 gases. First generation HUMs are modular in nature since they can be self-assembled from transition metal cations, ditopic linkers and inorganic "pillars", as exemplified by the prototypal variant, SIFSIX-3-Zn (3 = pyrazine, SIFSIX = SiF ). Conversely, HUMs that utilise chelating ligands such as ethylenediamine derivatives are yet to be explored as sorbents.

Enhancing Magnesium-Ion Storage in a Bi-Sn Anode through Dual-Phase Engineering.

Magnesium-ion batteries (MIBs) are a "beyond Li-ion" technology that are hampered by Mg metal reactivity, which motivates the development of anode materials such as tin (Sn) with high theoretical capacity (903 mAh g). However, pure Sn is inactive for Mg storage. Herein, Mg alloying with Sn is enabled within dual-phase Bi-Sn anodes, where the optimal composition (BiSn) outperformed single-phase Bi and Sn electrodes to deliver high specific capacity (462 mAh g at 100 mA g), good cycle life (84% after 200 cycles), and significantly improved rate capability (403 mAh g at 1000 mA g).

Hemilabile Binding of Acetylene in an Amide-Rich Ultramicroporous MOF Enables Strong Acetylene Selectivity.

Thanks to a hemilabile amide-based binding site, a previously unreported amide-functionalized metal-organic framework (MOF) exhibits high acetylene affinity over ethylene, methane, and carbon dioxide, three-in-one.

Structure-Property Correlations in CZTSe Domains within Semiconductor Nanocrystals as Photovoltaic Absorbers.

Semiconductor nanocrystals (NCs) are promising materials for various applications. Two of four recently identified CuZnSnSe (CZTSe) domains demonstrate metallic character, while the other two exhibit semiconductor character. The presence of both metallic and semiconductor domains in one NC can hugely benefit future applications.

Gate-opening Induced by C8 Aromatics in a Double Diamondoid Coordination Network.

Coordination networks (CNs) that undergo guest-induced structural transformations are of topical interest thanks to their potential utility in separations and storage applications. Herein, we report a double diamondoid () topology CN, [Ni(bimpz)(bdc)(HO)] or (Hbdc = 1,4-benzenedicarboxylic acid, bimpz = 3,6-bis(imidazol-1-yl)pyridazine), that undergoes structural transformations induced by C8 isomers, i.e.

Effect of Polymorphism on the Sorption Properties of a Flexible Square-Lattice Topology Coordination Network.

The stimulus-responsive behavior of coordination networks (CNs), which switch between closed (nonporous) and open (porous) phases, is of interest because of its potential utility in gas storage and separation. Herein, we report two polymorphs of a new square-lattice () topology CN, , of formula [Cu(Imibz)] (HImibz = {[4-(1-imidazol-1-yl)phenylimino]methyl}benzoic acid), isolated from the as-synthesized CN , which subsequently transformed to a narrow pore solvate, , upon mild activation (drying in air or heating at 333 K under nitrogen). contains MeOH in cavities, which was removed through exposure to vacuum for 2 h, yielding the nonporous (closed) phase .

Resolving Multielement Semiconductor Nanocrystals at the Atomic Level: Complete Deciphering of Domains and Order in Complex CuZnSnSe (CZTSe) Tetrapods.

Semiconductor nanocrystals (NCs) with high elemental and structural complexity can be engineered to tailor for electronic, photovoltaic, thermoelectric, and battery applications etc. However, this greater complexity causes ambiguity in the atomic structure understanding. This in turn hinders the mechanistic studies of nucleation and growth, the theoretical calculations of functional properties, and the capability to extend functional design across complementary semiconductor nanocrystals.

Crystal Engineering of a New Hexafluorogermanate Pillared Hybrid Ultramicroporous Material Delivers Enhanced Acetylene Selectivity.

Hybrid ultramicroporous materials (HUMs), metal-organic platforms that incorporate inorganic pillars, are a promising class of porous solids. A key area of interest for such materials is gas separation, where HUMs have already established benchmark performances. Thanks to their ready compositional modularity, we report the design and synthesis of a new HUM, , incorporating the ligand (4-(3,5-dimethyl-1-pyrazol-4-yl)pyridine, ) and GeF pillaring anions.

Anticancer Potential of Dendritic Poly(aryl ether)-Substituted Polypyridyl Ligand-Based Ruthenium(II) Coordination Entities.

This paper studies the anticancer potency of dendritic poly(aryl ether)-substituted polypyridyl ligand-based ruthenium(II) coordination entities. The dendritic coordination entities were successfully designed, synthesized, and characterized by different spectral methods such as Fourier transform infrared (FTIR), H and C- NMR, and mass spectrometry. Further, to understand the structure and solvation behavior of the coordination entities, we performed all-atom molecular dynamics (MD) simulations.

Shape-Memory Effect Enabled by Ligand Substitution and CO Affinity in a Flexible SIFSIX Coordination Network.

We report that linker ligand substitution involving just one atom induces a shape-memory effect in a flexible coordination network. Specifically, whereas SIFSIX-23-Cu, [Cu(SiF )(L) ] , (L=1,4-bis(1-imidazolyl)benzene, SiF =SIFSIX) has been previously reported to exhibit reversible switching between closed and open phases, the activated phase of SIFSIX-23-Cu , [Cu(SiF )(L ) ] (L =2,5-bis(1-imidazolyl)pyridine), transformed to a kinetically stable porous phase with strong affinity for CO . As-synthesized SIFSIX-23-Cu , α, transformed to less open, γ, and closed, β, phases during activation.

Hf-Based MOF for Rapid and Selective Sensing of a Nerve Agent Simulant and an Aminophenol: Insights from Experiments and Theory.

The metal-organic framework (MOF) Hf-DUT-52 was prepared with diamino functionality by the solvothermal method. This material displayed fluorometric sensing ability toward a nerve agent simulant (diethyl chlorophosphate (DCP)) and 3-diethylaminophenol (3-DEAP). It is the first-ever reported fluorescent MOF sensor for DCP and 3-DEAP.

Role of decomposition products in the oxidation of cyclohexene using a manganese(III) complex.

Metal complexes are extensively explored as catalysts for oxidation reactions; molecular-based mechanisms are usually proposed for such reactions. However, the roles of the decomposition products of these materials in the catalytic process have yet to be considered for these reactions. Herein, the cyclohexene oxidation in the presence of manganese(III) 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine chloride tetrakis(methochloride) (1) in a heterogeneous system via loading the complex on an SBA-15 substrate is performed as a study case.

One Atom Can Make All the Difference: Gas-Induced Phase Transformations in Bisimidazole-Linked Diamondoid Coordination Networks.

Coordination networks (CNs) that undergo gas-induced transformation from closed (nonporous) to open (porous) structures are of potential utility in gas storage applications, but their development is hindered by limited control over their switching mechanisms and pressures. In this work, we report two CNs, [Co(bimpy)(bdc)] () and [Co(bimbz)(bdc)] () (Hbdc = 1,4-benzendicarboxylic acid; bimpy = 2,5-bis(1H-imidazole-1-yl)pyridine; bimbz = 1,4-bis(1H-imidazole-1-yl)benzene), that both undergo transformation from closed to isostructural open phases involving at least a 27% increase in cell volume. Although and only differ from one another by one atom in their -donor linkers (bimpy = pyridine, and bimbz = benzene), this results in different pore chemistry and switching mechanisms.

A Robust Molecular Porous Material for C H /CO Separation.

A molecular porous material, MPM-2, comprised of cationic [Ni (AlF )(pzH) (H O) ] and anionic [Ni Al F (pzH) (H O) ] complexes that generate a charge-assisted hydrogen-bonded network with pcu topology is reported. The packing in MPM-2 is sustained by multiple interionic hydrogen bonding interactions that afford ultramicroporous channels between dense layers of anionic units. MPM-2 is found to exhibit excellent stability in water (>1 year).

Modeling Polyzwitterion-Based Drug Delivery Platforms: A Perspective of the Current State-of-the-Art and Beyond.

Drug delivery platforms are anticipated to have biocompatible and bioinert surfaces. PEGylation of drug carriers is the most approved method since it improves water solubility and colloid stability and decreases the drug vehicles' interactions with blood components. Although this approach extends their biocompatibility, biorecognition mechanisms prevent them from biodistribution and thus efficient drug transfer.

Enhanced Photocatalytic Hydrogen Evolution from Water Splitting on TaO/SrZrO Heterostructures Decorated with CuO/RuO Cocatalysts.

Photocatalytic H generation by water splitting is a promising alternative for producing renewable fuels. This work synthesized a new type of TaO/SrZrO heterostructure with Ru and Cu (RuO/CuO/TaO/SrZrO) using solid-state chemistry methods to achieve a high H production of 5164 μmol g h under simulated solar light, 39 times higher than that produced using SrZrO. The heterostructure performance is compared with other TaO/SrZrO heterostructure compositions loaded with RuO, CuO, or Pt.

Elucidation of Structure-Activity Relations in Proton Electroreduction at Pd Surfaces: Theoretical and Experimental Study.

The structure-activity relationship is a cornerstone topic in catalysis, which lays the foundation for the design and functionalization of catalytic materials. Of particular interest is the catalysis of the hydrogen evolution reaction (HER) by palladium (Pd), which is envisioned to play a major role in realizing a hydrogen-based economy. Interestingly, experimentalists observed excess heat generation in such systems, which became known as the debated "cold fusion" phenomenon.

Surprisingly Low Reactivity of Layered Manganese Oxide toward Water Oxidation in Fe/Ni-Free Electrolyte under Alkaline Conditions.

So far, many studies on the oxygen-evolution reaction (OER) by Mn oxides have been focused on activity; however, the identification of the best performing active site and corresponding catalytic cycles is also of critical importance. Herein, the real intrinsic activity of layered Mn oxide toward OER in Fe/Ni-free KOH is studied for the first time. At pH ≈ 14, the onset of OER for layered Mn oxide in the presence of Fe/Ni-free KOH happens at 1.

The First Sulfate-Pillared Hybrid Ultramicroporous Material, SOFOUR-1-Zn, and Its Acetylene Capture Properties.

Hybrid ultramicroporous materials, HUMs, are comprised of metal cations linked by combinations of inorganic and organic ligands. Their modular nature makes them amenable to crystal engineering studies, which have thus far afforded four HUM platforms (as classified by the inorganic linkers). HUMs are of practical interest because of their benchmark gas separation performance for several industrial gas mixtures.