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Inorganic zeolites have excellent molecular sieving properties, but they are difficult to process into macroscopic structures. In this work, we use metal–organic framework (MOF) glass as substrates to engineer the interface with inorganic zeolites, and then assemble the discrete crystalline zeolite powders into monolithic structures. The zeolites are well dispersed and stabilized within the MOF glass matrix, and the monolith has satisfactory mechanical stabilities for membrane applications. We demonstrate the effective separation performance of the membrane for 1,3‐butadiene (C4H6) from other C4 hydrocarbons, which is a crucial and challenging separation in the chemical industry. The membrane achieves a high permeance of C4H6 (693.00±21.83 GPU) and a high selectivity over n‐butene, n‐butane, isobutene, and isobutane (9.72, 9.94, 10.31, and 11.94, respectively). This strategy opens up new possibilities for developing advanced membrane materials for difficult hydrocarbon separations. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) with non‐blinking applied in bio‐imaging is important for understanding cellular dynamics by monitoring single particles in living cells. Antibunching is once believed to be applied to identify a single QD, which shows a strong dependence on the atom or ion number. However, recent works indicate that the antibunching alone may not be sufficient to demonstrate that the fluorescence comes from a single QD. To some extent, it is neither necessary nor sufficient for a single QD, though it is absolutely right for a single atom because a single QD is composed of thousands of atoms, which in principle are favorable to the formation of multi‐excitonic states. Blinking behavior, almost unobservable in ensembles due to the averaging, is characteristic of the single QD which owns the quantum effect due to its discrete energy levels. Here, a method of transformation of a single graphene quantum dot from non‐blinking to blinking via catalytic reaction to identify a single QD is reported, which can also help with understanding the catalytic dynamics of a single QD, which is a complementary means of confirming a single QD. The reported technique paves the way to understanding a single QD and its catalytic and kinetic behaviors. [ABSTRACT FROM AUTHOR]

Highlights: Recent advances in the metal–organic framework (MOF)-related catalysts for electrochemical ammonia synthesis protocols under ambient reaction conditions are summarized and discussed. The design and fabrication of efficient electrocatalysts from MOF for the reduction of N2 and NO3− are systematically analyzed. Based on the current advances, the ongoing challenges and promising perspectives are highlighted. Electrocatalytic synthesis under mild conditions has become increasingly important as one of the practical alternatives for industrial applications, especially for the green ammonia (NH3) industry. A properly engineered electrocatalyst plays a vital role in the realization of superior catalytic performance. Among various types of promising nanomaterials, metal–organic frameworks (MOFs) are competitive candidates for developing efficient electrocatalytic NH3 synthesis from simple nitrogen-containing molecules or ions, such as N2 and NO3−. In this review, recent advances in the development of electrocatalysts derived from MOFs for the electrosynthesis of NH3 are collected, categorized, and discussed, including their application in the N2 reduction reaction (NRR) and the NO3− reduction reaction (NO3RR). Firstly, the fundamental principles are illustrated, such as plausible mechanisms of NH3 generation from N2 and NO3−, the apparatus of corresponding electrocatalysis, parameters for evaluation of reaction efficiency, and detection methods of yielding NH3. Then, the electrocatalysts for NRR processes are discussed in detail, including pristine MOFs, MOF-hybrids, MOF-derived N-doped porous carbons, single atomic catalysts from pyrolysis of MOFs, and other MOF-related materials. Subsequently, MOF-related NO3RR processes are also listed and discussed. Finally, the existing challenges and prospects for the rational design and fabrication of electrocatalysts from MOFs for electrochemical NH3 synthesis are presented, such as the evolution of investigation methods with artificial intelligence, innovation in synthetic methods of MOF-related catalysts, advancement of characterization techniques, and extended electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

Halide double perovskites [A2MIMIIIX6] are an important class of materials that have garnered substantial interest as non‐toxic alternatives to conventional lead iodide perovskites for optoelectronic applications. While numerous studies have examined chloride and bromide double perovskites, reports of iodide double perovskites are rare, and their definitive structural characterization has not been reported. Predictive models have aided us here in the synthesis and characterization of five iodide double perovskites of general formula Cs2NaLnI6 (Ln=Ce, Nd, Gd, Tb, Dy). The complete crystal structures, structural phase transitions, optical, photoluminescent, and magnetic properties of these compounds are reported. [ABSTRACT FROM AUTHOR]

Here, we report kinetic studies using electron spin resonance spectroscopy on spin catalysis reactions caused by using graphene belts which were synthesized by a radical coupling method. The results show that σ‐type free radical species provide the dominant sites for catalytic activity through the spin‐spin interaction, although there are some other influencing factors. The spin catalysis mechanism can be applied both in the oxygen reduction reaction (ORR) and in organic synthesis. The graphene belt spin catalyst shows excellent performance with a high ORR half‐wave potential of 0.81 V and long‐term stability with almost no loss of activity after 50 000 cycles in alkaline media. It also shows excellent performance in a benzylamine coupling with molecular oxygen to generate the corresponding imine at an average conversion of ≈97.7 % and an average yield of ≈97.9 %. This work opens up a new research direction for understanding aerobic processes in the field of spin catalysis. [ABSTRACT FROM AUTHOR]

Oxides of molybdenum, MoOx, have a rich structural chemistry arising from the accommodation of oxygen deficiency as MoO3 is reduced and varied redox behavior arising from the ability of Mo to take on several different oxidation states. We review MoO3, MoO2, and all the reduced Mo oxides with intermediate compositions for their performance as Li-ion battery electrode materials. These reduced oxides are perhaps the most structurally diverse in the field of energy storage materials, taking on structures ranging from ones with crystallographic shear to bronze-like structures and distorted rutile. The crystal structure can have a significant impact on the performance of battery materials, which makes the reduced Mo oxides a promising domain of study. Electrochemical studies of these oxides from as early as 1971 to as recently as 2022 are compiled, and characteristics of capacity, capacity retention, and rate performance are compared. We find that certain oxides indeed display promising and highly reversible capacities for Li+ storage. Typical redox voltages for Mo oxides lie in a regime that hinders maximizing energy density when they are paired with higher-voltage cathodes or lower-voltage anodes. The possibility of decreasing the redox voltage in the future will expand the promise of these materials while offering an alternative to more critical elements such as Nb. [ABSTRACT FROM AUTHOR]

Perovskite-related materials show very promising properties in many fields. Pb-free perovskites are particularly interesting, because of the toxicity of Pb. In this study, hybrid double perovskite MA2KBiCl6 (MA = methylammonium cation) was found to have interesting variable temperature behaviours. Both variable temperature single crystal X-ray diffraction, synchrotron powder diffraction, and Raman spectroscopy were conducted to reveal a rhombohedral to cubic phase transition at around 330 K and an order to disorder transition for inorganic cage below 210 K. [ABSTRACT FROM AUTHOR]

Chiral hybrid metal halides with a high dissymmetry factor (glum) and a superior photoluminescence quantum yield (PLQY) are promising candidates for circularly polarized luminescence (CPL) light sources. Here, we report eight new chiral hybrid manganese halides, crystallizing in the non‐centrosymmetric space group P212121 and showing intense CPL emissions. Oppositely‐signed circular dichroism (CD) and CPL signals are detected according to the R‐ and S‐configurations of the chiral alkanolammonium cations. Time‐resolved PL spectra show long averaged decay lifetimes up to 1 ms for (R‐3‐quinuclidinol)MnBr3 (R‐1). The glum of polycrystalline samples for coordinated structures (23×10−3) is more than doubled compared with the non‐coordinated ones (8.5×10−3), due to the structural variations. R‐1 exhibit both a high glum and a high PLQY (50.2 %). The effective chirality transfer mechanism through coordination bonds, with strongly emissive MnII centers, enables a new class of high‐performance CPL materials. [ABSTRACT FROM AUTHOR]

The article discusses the importance of high-performing and scalable adsorbent materials in addressing the global demand for energy and mitigating the consequences of burning fossil fuels. Adsorbent materials have porous atomic crystal structures that enable the capture and storage of certain gases at useful temperatures and pressures. The article focuses on a specific material called aluminum formate (ALF), which has shown promise in capturing CO2 and storing hydrogen gas. ALF's simple preparation from commodity chemicals and low cost make it a viable solution for CO2 capture and grid-scale H2 storage. However, ALF's instability in humid conditions and the question of what to do with potentially massive quantities of ALF are challenges that need to be addressed. The article also highlights ALF's ability to separate gases and store appreciable amounts of H2 gas at moderate temperatures and pressures, making it a potential solution for large-scale grid-scale H2 storage. [Extracted from the article]

The synthesis and crystal structures of two transition metal-based (Zn, Ni) coordination polymers comprising ligand molecules formed during hydrothermal treatment is described. The process involves dimerization via C-N bond formation for zinc, and C-C bond formation for nickel.