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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 (7a/7b) 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.

The front cover shows photoinduced electron and energy transfer pathways in all perylene diimide-derived, wide-band capturing donor-acceptor conjugates as a mimicry of the early events of natural photosynthesis. Selective excitation of the charge transfer band in these conjugates leads to an initial singlet charge transfer excited state that undergoes subsequent electron transfer involving linked perylene diimide, resulting in efficient charge separation. More details can be found in the Research Article by Fernando Fernández-Lázaro, Francis D'Souza, and co-workers (DOI: 10.1002/cplu.202400348).

The cover feature shows amino-functionalized (blue gloves) assisting enhanced CO₂ uptake compared to unfunctionalized (white gloves) MOFs. The amino-functionalized MOF holds 3 CO₂ molecules while the unfunctionalized MOF holds only 2 CO₂ molecules, according to the ratio of adsorption capacities at 273 K at 1 bar. The recorded gas adsorption isotherms at 273 K are shown in the background highlighting the affinity of MOFs for CO₂ over N₂. More details can be found in the Research Article by Sachin Maruti Chavan and co-workers (DOI: 10.1002/cplu.202400107).

Acetylene is in-demand even on Titan! The cover picture shows Titan - the moon of Saturn. Titan is unique in having an atmosphere and hydrocarbons. Acetylene was discovered on Titan, but its amount constantly decreases over time, which may indicate its consumption by living organisms. On Earth, acetylene is a ton-scale product of the chemical industry. Methods for manufacturing acetylene and the cost of each method can be found in the Review by Konstantin Rodygin and co-workers (DOI: cplu.202400247). Cover design by Andrei Lebedev.

The sustainable synthesis of urea from ammonia (NH3) and carbon dioxide (CO2) using ultraporous permanently polarized hydroxyapatite (upp-HAp) as catalyst has been explored as an advantageous CO2-revalorization strategy. As the simultaneous activation of N2 and CO2 (single-step) demands an increase of the reaction conditions, we have re-visited the industrial two-step Bazarov reaction. upp-HAp has been designed as a stable multifunctional catalyst capable of promoting both CO2 and NH3 adsorption for their subsequent C-N bond formation. Herein we report the synthesis of 1 mmol/gcat of urea with a selectivity of 97% under strictly mild conditions (95-120 ºC and 1 bar of CO2; without applying any electrical currents or UV irradiation) which represents an efficiency of ~2% and ~30% with respect to the NH3 and CO2 content, respectively. The study of the NH3 content, products adsorbed in the catalyst, presence of intermediates and temperature of the reaction allows unveiling the great potential of upp-HAp as a green catalyst for sustainable Bazarov reactions. Results suggest that the double-step approach could be more advantageous for both synthesizing urea and as a CO2-revalorization strategy, which in turn promotes the development of specific technologies for the independent synthesis of green NH3.

New chemical compositions and structures for medium- and high-entropy oxides (HEOs) currently represent a promising new avenue in materials research for a wide range of applications including catalysis, energy storage, and ceramics.  To speed up further development, synthesis methods for multicationic oxides are needed for controlling features like morphology, porosity, and chemical compositions. In this work, mesoporous spinel oxide spheres with five cations are synthesized using solvothermal synthesis techniques. The targeted chemistry included Co, Al, Fe, and Cr as the first four cations, where the fifth cation was varied by increasing cation radii (Ga, In, Yb, Ho, or Ce).  After calcination, all as-synthesized precursors led to mesoporous oxide spheres with spinel oxide structures. In order to demonstrate an example of applicability for targeting different M3+ cations, the sample containing Co, Al, Fe, Cr, and In was tested in a model reaction of thermocatalytic CO2 hydrogenation and is shown to be active with a preference to methanol formation (58% selectivity, 7.8% conversion at 300 °C). The synthesis of multicationic mesoporous spheres appears to be quite flexible in terms of possible M3+ cations compositions and is a potential material to combine targeted chemistry for applications like catalysis.

The research and development of push-pull tetraene chromophores (PPT-phores) have contributed greatly to the field of organic electro-optic (EO) materials and devices since the inauguration of CLD-1 in 2001. This study is thus a systematic contribution to synthesize and characterize a series of centro-arylated PPT-phores based on strong electron-donating tetrahydroquinolinyl groups and variable strong electron-accepting tricyanofuran derivatives. In particular, we report the crystallographic data to show various packing modes of these PPT-phores with detailed information about bond length alternation and intermolecular interactions, the optical absorption edges of guest-host polymers by the Tauc model, and the anisotropy and dispersion of Pockels tensors for the poled polymers by attenuated total reflection spectroscopy. Such analyses have not been addressed to any significant extent previously and are fundamentally important to the future development of PPT-phore-based EO materials and devices. The poled films of several centro-arylated PPT-phores in polycarbonates exhibited large EO activities, excellent thermal stability, and tunable optical transparency at the telecom O- and C-band. The study demonstrates the effectiveness of π-bridge centro-arylation enabled by molecular shape modification and rigidity enhancement, over the relatively flexible and labile thioether or alkoxy groups, in rational design of hyperpolarizable PPT-phores for high-performance EO polymers.