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Atomically ordered intermetallic Pt-based nanoparticles, recognized as advanced electrocatalysts, exhibit superior activity for the oxygen reduction reaction (ORR) in fuel cell cathodes. Nevertheless, the formation of these ordered structures typically necessitates elevated annealing temperatures, which can accelerate particle growth and diminished reactivity. In this study, we synthesized carbon-supported platinum-cobalt intermetallic compounds (PtCo-IMCs) with sub-4 nm particle sizes and uniform distribution. These catalysts, characterized by high platinum content and exceptional ORR activity, are specifically tailored for heavy-duty vehicle (HDV) applications. The PtCo-IMCs exhibited significantly enhanced catalytic performance and durability compared to conventional Pt-based catalysts, utilizing platinum nanoparticles as nucleation sites to promote growth. This method effectively retained smaller particle sizes while achieving a higher degree of ordering and alloying during high-temperature annealing. Optimization of the annealing temperature resulted in peak activity and stability at 800 °C. The mass activity (MA) of the PtCo-800 catalyst was 2.7-fold and 1.8-fold that of the commercial Pt/C and disordered PtCo catalysts, respectively. Additionally, the single cell employing the PtCo-800 catalyst showed a minimal voltage loss of only 27 mV at a current density of 2 A cm⁻² after 30,000 cycles of the accelerated durability test (ADT), underscoring its long-term stability. This work provides an efficient method for the preparation of high loading ORR electrocatalyst with excellent durability.

The poorly understood factors controlling the reactivity and selectivity (both stereo- and enantioselectivity) of catalyzed Diels-Alder reactions involving cyclobutenones as dienophiles have been analyzed in detail by means of Density Functional Theory calculations. To this end, the reactions with cyclopentadiene and furan as dienes and 3-(methoxycarbonyl)cyclobutenone catalyzed by Corey's chiral oxazaborolidium ion (COBI) have been selected and compared to their analogous uncatalyzed transformations. The combined Activation Strain Model of reactivity and Energy Decomposition Analysis methods have been used to quantitatively understand the acceleration and selectivity induced by the catalyst in this reaction.

Luminescent polymers have gained considerable research effects in different fields, which are generally prepared by incorporating traditional luminescent moieties. In recent years, non-traditional intrinsic luminescent (NTIL) polymers containing no traditional luminescent moieties have been reported, which have attracted broad attention. This review summarizes recent advances in multicolor NTIL polymers, including stimuli-responsive NTIL polymers, multicolor luminescence of NTIL polymers through polymerization-induced emission strategy or molecular structure modulation, and the positive influence of through-space charge-transfer effect and hydrogen bonding construction strategy on NTIL polymers. This review on NTIL polymers may cause inspirations in different fields.

The light-induced control in the fabrication of materials is a field in continuous development. So far, photo-induced processes have been used mostly for organic polymeric materials. However, there is a recent, increasing interest in exploring the possibility of using these techniques to induce the precipitation of inorganic materials. This perspective paper outlines the main principles of the light-induced precipitation of inorganic materials, focusing on the recent papers published in this field. The description of the mechanisms and the materials involved in these light-induced processes highlight their many possibilities and future challenges, which could pave the way for significant advancements in this exciting technology.

The mechanisms of Co(III)-catalyzed annulations of N-chlorobenzamide with olefins bearing different electronic properties were computationally studied and the origins of regioselectivity reversal were investigated by using energy decomposition analysis (EDA). The alkene migratory insertion step determines the regiochemistry of these reactions. EDA results indicate that the 2,1-insertion with styrene is favored because there is a weaker Pauli repulsion between the cobaltacycle Co−C σ orbital and the olefin π orbital. Conversely, the 1,2-insertion with vinyltrimethylsilane is more favorable than the 2,1-insertion. This is mostly because the increased π electron density can effectively differentiate the stabilizing electronic interactions.

Three unsymmetric fluorophores differing in their flanking electron acceptor (−NO₂, −CN, −CHO) were investigated for their electrofluorochromism and electrochromism. The emission yield of the -NO₂ substituted fluorophore in the solid state was ca. 9-fold less than its -CN and -CHO counterparts. Visible color changes of the fluorophores were observed with an applied potential. The intensity of the near-infrared absorption at ca. 1500 nm formed upon electrochemical oxidation was contingent on the electron-withdrawing group: 2-fold more intense with the -CN substitution than its -H counterpart. The coloration efficiency was upwards of 655 cm² C⁻¹ and the bleaching kinetics (t_b; 22 s) of the NIR band decreased according to -NO₂>-CN>- CHO ≈ -H. The electrochemically generated states could be reversibly formed during 120 min of switching the applied potential. The contrast ratio of the radical cation and the NIR absorption was near unity and 60–82 %, respectively. The photoemission intensity of the fluorophores could also be modulated with applied potentials. The collective electrochemically mediated color switching and emission intensity modulation along with their solid-state emission demonstrate that benzothiadiazole fluorophores can play a dual role in chromic devices both as the color switching and photoemission intensity modulating material.

Electrochemical reduction reaction of CO₂ (eCO₂RR) to produce valuable chemicals offers an attractive strategy to solve energy and environmental problems simultaneously. We have mapped out entire reaction pathways of eCO₂RR to CO on Cu(100), including all intermediates and transition states using first-principles simulations. To accurately account for the solvent effect, the reaction was investigated with and without explicit water molecules, highlighting the limitations of the often (mis)used vacuum reaction pathway simplification. The results show that the reduction reaction was initiated under neutral pH conditions at an applied potential of −0.11 V (RHE, reversible hydrogen electrode) and all elementary reactions were thermodynamically favorable, while an applied potential of −1.24 V is required to ensure that all reactions exhibit spontaneous behavior. Detailed analysis revealed that solvation significantly influences the stability of the adsorbates and intermediates. Its inclusion notably alters the calculated reaction kinetics and energetic parameters by lowering the barrier energies and Gibbs free energies of all reactions. CO production proceeded mainly via the COOH* pathway (CO₂ →trans-COOH*→cis-COOH*→CO*+OH*→CO*→CO). The use of water as a more sustainable and cost-effective solvent is compared to other options such as organic solvents, ionic liquids and mixed solvent systems, which are less sustainable and more expensive.

We present a computational study of the structure and of the transport properties of electrolytes based on Li[(CF₃SO₂)₂N] solutions in mixtures of sulfoxides and sulfones solvents. The simulations of the liquid phases have been carried out using molecular dynamics with a suitably parametrized model of the intermolecular potential based on a polarizable expression of the electrostatic interactions. Pulse field gradient NMR measurements have been used to validate and support the computational findings. Our study show that the electrolytes are characterized by extensive aggregation phenomena of the support salt that, in turn, determine their performance as conductive mediums.

Reactions of bipyridyl-functionalized imidazole-thiones and selones with MeX (X=I, OTf) afforded sulfenyl and selenenyl cations [(NNC)EMe]X (2/3, E=S, Se). Further reactions of these main-group cations with [Cu(CH₃CN)₄]BF₄, Cu(OTf) furnished dicationic [{Cu(μ-I)(NNC)EMe}₂][Y]₂ (5/6, Y=BF₄, OTf) and tricationic copper(I) complexes [Cu{(NNC)EMe}₂](OTf)₂BF₄ (7 a/7 b) when employed [(NNC)EMe]I and [(NNC)EMe]OTf respectively. All these cationic complexes were characterized by various spectroscopic techniques, including X-ray diffraction analysis. The solid-state structures revealed novel bonding modes of the cations. The cationic nature of new complexes was analyzed by the ⁷⁷Se NMR spectroscopy, which indicated different electronic environments around the selenium centers. The cations [(NNC)EMe]X (X= I, OTf), and (NNC)SMe bearing copper complex [{Cu(μ-I)(NNC)EMe}₂][Y]₂ proved as potential candidates for alkylation of various Lewis bases and as molecular catalyst in aldehyde-alkyne-amine coupling reactions, respectively. The latter catalytic reactions yielded a range of three-component products in good to excellent yields with low catalyst loading under solvent-free conditions, which demonstrate the potential utility of group-16 cations as ancillary ligands in homogeneous catalysis.

The world of lubricants is driven by the constant pursuit of improved performance in response of the requests of new engine generations. Engine oils play a critical role as lubricants in mitigating wear, reducing friction and ensuring optimal engine operation under diverse conditions. Modern commercial engine oils are complex formulations, comprising of a base oil, generally coming from petroleum sources, formulated with specific, important additives able to optimize the viscosity, thickening and shear stress in the operating temperature range. Such additives are produced in the thousand tons per year scale range. The most important class of additives for modern lubrication is made of organic polymers with variable architectures and topologies, generally referred as “viscosity modifiers” (VMs): they act as “moderators” of viscosity at different working temperatures. The tremendous advances in polymer science have been reflected in the realm of VMs, allowing the commercialization of products obtained by controlled polymerization techniques, and the experimentation of a broad variety of different macromolecular architectures and topologies as VMs. In this review we introduce the reader, together with the basic principles of viscosity modification and thermal-dependent rheological response, to the fascinating chemistry towards the improvement of VMs, through optimization of macromolecular design and architecture.