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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.

Metal ion detection is of a paramount importance for health monitoring. The host should properly accommodate the desired ion and be selective with respect to other potential guests, which makes devising ion sensors a demanding task. Recently (Phys. Chem. Chem. Phys. 2023, 25, 32656), we suggested a procedure for a computational design of crown ethers that can capture magnesium ions. In the present contribution we apply the same approach to search for Mg2+ trap with thiophene units, in accord with proposed hosts for Na+ and K+ ions (Adv. Funct. Mater., 2016, 26, 514). Additionally, we present a procedure based on the combination of Density Functional Theory based Molecular Dynamics and the Interacting Quantum Fragments methodology for determination of host-guest interaction and binding energies in a model with a large number of explicit solvent molecules. The presented strategy could be applied for identification of the right host for an arbitrary guest.

The invention of laminated safety glass is attributed to the French chemist and artist Edouard Benedictus (1878-1930), who developed the innovation known as Triplex glass after inspiration struck via a fortuitous laboratory accident. Licensed first to the English Triplex Safety Glass Company in 1912, with production later carried out in the US, Triplex glass was first applied to automobiles during the first World War. While the story of his lab accident can be found in many sources, it has become more legend than historical fact. To rectify this, a more accurate account of Benedictus and the development of Triplex glass is presented based on historical records.

Vibrational spectroscopy can be said to have started with the seminal work of Coblentz in the 1900s, who recorded the first recognisable infrared spectra. Today, vibrational spectroscopy is ubiquitous and there are many ways to measure a vibrational spectrum. But this is usually only the first step, almost always there is a need to assign the resulting spectra: "what property of the system results in a feature at this energy"? How this question has been answered has changed over the last century, as our understanding of the fundamental physics of matter has evolved. In this Perspective, I will present my view of how the analysis of vibrational spectra has evolved over time. The article is divided into three sections: past, present and future. The "past" section consists of a very brief history of vibrational spectroscopy. The "present" is centered around ab initio studies, particularly with density functional theory (DFT) and I will describe how this has become almost routine. For the "future", I will extrapolate current trends and also speculate as to what might come next.

Nanoparticles of metal-organic frameworks (nanoMOFs) possess the unusual combination of both internal and external surfaces. While internal surfaces have been the focus of fundamental and applications-based MOF studies, the chemistry of the external surfaces remains scarcely understood. Herein we report that specific ion interactions with nanoparticles of Cu(1,2,3-triazolate)₂ (Cu(TA)₂) resemble the Hofmeister behavior of proteins and the supramolecular chemistry of synthetic macromolecules. Inspired by these anion-selective interactions, we tested the performance of Cu(TA)₂ nanoparticles as chemical field effect transistor (ChemFET) anion sensors. Rather than size-based selectivity, the detection limits of the devices exhibit a Hofmeister trend, with the greatest sensitivity towards anions perchlorate, iodide, and nitrate. These results highlight the importance of the pore-based supramolecular interactions, rather than localized donor-acceptor pairs, in designing MOF-based technologies.

Domestic dishwashers have become an integral part of modern households, offering convenience and effective cleaning. However, efforts to reduce energy and water consumption have resulted in longer wash programmes, which, despite their high cleaning performance, are not well accepted by consumers due to their long durations. While these eco-programmes are presumed to be well-optimized in terms of their structural components, the role of detergents has been somewhat overlooked, despite their significant contribution to both the cleaning and hygiene performance of domestic dishwashers. Beyond machine parameters, the chemical composition of detergents is crucial in improving the cleaning, drying and hygiene performance of household dishwashers, as they contain various components - such as surfactants, enzymes, and bleaching agents - that interact with soil residues to improve cleaning effectiveness. This review will focus on recent scientific efforts to optimize programme structures concerning cycle durations and energy consumption and the role of detergents in this interrelationship between cleaning, drying and hygiene.

Fuel cells are recognized as promising alternatives to existing conventional energy systems for a sustainable future. However, the synthesis of efficient and robust platinum (Pt) based catalysts remains a challenge for practical fuel cell applications. Herein, the Pt3Co/C nanoparticles with about 4.45 nm are firstly prepared by a pre-lithiation-deposition strategy on C carrier and used as efficient electrocatalysts for cathodic oxygen reduction reaction. Notably, after heat treatment at 600 ℃, the obtained Pt3Co/C-600 catalyst shows excellent mass and specific activities (MA and SA) of 0.69 A mgPt-1 and 1.01 mA cmPt-2, respectively, which are more than one order of magnitude higher than that of Pt/C-600. In particular, after accelerated durability testing with 20k cycles, the durability of the Pt3Co/C-600 catalyst (98.3% retention of MA) is much higher than that of Pt3Co/C-600 without pre-lithiation (42.5% retention of MA). The alloying of Pt and Co and the use of pre-lithiation to enable strong interactions between the carbon carriers and the Pt-Co nanoparticles contributed to the increased activity and excellent stability. This work provides a new perspective for the development of high-performance and low-cost Pt alloy electrocatalysts.

Understanding and exploring the existence of a recognizable boundary between the noncovalent tetrel bond (TtB) and the coordination or weakened covalent bond are important for the bonding characterization. We have developed a simple methodology for analysing the type of bonds based on comparison of the electrostatic and total static potentials along the bond line. For the typical σ-hole noncovalent bond formed by a Tt atom in a tetrahedral molecule, we have found that the space gap between positions of the maxima of the total static potential and the negative quantity of electrostatic potential is much wider than that for the coordination bonds in a trigonal bipyramid molecular system for the Cl-Tt/Cl⋅⋅⋅Tt and N-Tt/N⋅⋅⋅Tt (Tt=C, Si, Ge) bonds in molecules and molecular complexes. The distinction between the weakened covalent and strengthened noncovalent bonds is well reflected in behaviour of the Fermi hole along the bond line. Two-factor empirical rule based on the superposition of the electrostatic and total static potentials is suggested.

Long-chain bio-based polyamide has shown promising development prospects due to its excellent properties and green renewable characteristics; however, synthesizing inherently flame-retardant long-chain bio-based polyamide remains a big challenge due to the lack of effective knowledge of the key polymerization process. Herein, intrinsicly flame-retardant long-chain bio-based polyamide 512 (PA512) was synthesized in the presence of a reactive flame retardant with high thermal stability and good water solubility. The reaction conditions and existing problems in each stage of the copolymerization system have been clarified and optimized. By utilizing a two-step pre-polymerization approach, a series of intrinsicly flame-retardant PA512 (FRPA512) with large molecular weight, high phosphorus element content and good mechanical properties were obtained. More importantly, the prepared FRPA512 with 5 wt % flame retardant loading exhibited good flame retardancy, showing a limiting oxygen index (LOI) of 28.1 % and a vertical burning rating of V-0. This study provides a feasible solution to the common problem in the synthesis of flame-retardant polyamides, while also offering new insights for future modification of polyamide copolymerization.