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Photoswitches are molecular systems that are chemically transformed subsequent to interaction with light and they find potential application in many new technologies. The design and discovery of photoswitch candidates require intricate molecular engineering of a range of properties to optimize a candidate to a specific applications, a task which can be tackled efficiently using quantum chemical screening procedures. In this paper, we perform a large scale screening of approximately half a million bicyclic diene photoswitches in the context of molecular solar thermal energy storage using ab initio quantum chemical methods. We further device an efficient strategy for scoring the systems based on their predicted solar energy conversion efficiency and elucidate potential pitfalls of this approach. Our search through the chemical space of bicyclic dienes reveals systems with unprecedented solar energy conversion efficiencies and storage densities that show promising design guidelines for next generation molecular solar thermal energy storage systems. [ABSTRACT FROM AUTHOR]

Dual‐ion batteries (DIBs) is a promising technology for large‐scale energy storage. However, it is still questionable how material structures affect the anion storage behavior. In this paper, we synthesis graphite with an ultra‐large interlayer distance and heteroatomic doping to systematically investigate the combined effects on DIBs. The large interlayer distance of 0.51 nm provides more space for anion storage, while the doping of the heteroatoms reduces the energy barriers for anion intercalation and migration and enhances rapid ionic storage at interfaces simultaneously. Based on the synergistic effects, the DIBs composed of carbon cathode and lithium anode afford ultra‐high capacity of 240 mAh g−1 at current density of 100 mA g−1. Dual‐carbon batteries (DCBs) using the graphite as both of cathode and anode steadily cycle 2400 times at current density of 1 A g−1. Hence, this work provides a reference to the strategy of material designs of DIBs and DCBs. [ABSTRACT FROM AUTHOR]

Organosulfides are promising candidates as cathode materials for the development of electric vehicles and energy storage systems due to their low‐cost and high capacity properties. However, they generally suffer from slow kinetics because of the large rearrangement of S−S bonds and structural degradation upon cycling in batteries. In this paper, we reveal that soluble bis(2‐pyrimidyl) disulfide (Pym2S2) can be a high‐rate cathode material for rechargeable lithium batteries. Benefiting from the superdelocalization of pyrimidyl group, the extra electrons prefer to be localized on the π* (pyrimidyl group) than σ* (S−S bond) molecular orbitals initially, generating the anion‐like intermedia of [Pym2S2]2− and thus decreasing the dissociation energy of the S−S bond. It makes the intrinsic energy barrier of dissociative electron transfer depleted, therefore the lithium half cell exhibits 2000 cycles at 5 C. This study provides a distinct pathway for the design of high‐rate, long‐cycle‐life organic cathode materials. [ABSTRACT FROM AUTHOR]

Cupin proteins share a double‐stranded β‐helix fold, form one of the largest protein superfamilies, and possess remarkable functional diversity. They usually exist in homooligomeric states. Goss and co‐workers recently reported that the cupin protein Pac13, which is a dehydratase that mediates the formation of the 3′‐deoxy nucleoside of pacidamycins, is an unusual small monomer. However, a careful analysis of the biophysical and structural data provided by the authors suggests that Pac13 is in fact a homodimer, similar to many other cupin proteins. [ABSTRACT FROM AUTHOR]

The controlled electrochemical reduction of carbon dioxide to value added chemicals is an important strategy in terms of renewable energy technologies. Therefore, the development of efficient and stable catalysts in an aqueous environment is of great importance. In this context, we focused on synthesizing and studying a molecular MnIII‐corrole complex, which is modified on the three meso‐positions with polyethylene glycol moieties for direct and selective production of acetic acid from CO2. Electrochemical reduction of MnIII leads to an electroactive MnII species, which binds CO2 and stabilizes the reduced intermediates. This catalyst allows to electrochemically reduce CO2 to acetic acid in a moderate acidic aqueous medium (pH 6) with a selectivity of 63 % and a turn over frequency (TOF) of 8.25 h−1, when immobilized on a carbon paper (CP) electrode. In terms of high selectivity towards acetate, we propose the formation and reduction of an oxalate type intermediate, stabilized at the MnIII‐corrole center. [ABSTRACT FROM AUTHOR]

In their Correspondence, Sergey V. Krivovichev and Luca Bindi argue that the novel excellent nonlinear optical material antimony pyrophosphate, K2Sb(P2O7)F, reported in our Research Article published in this journal belongs to the fresnoite Ba2[TiO(Si2O7)] group and its structure is not novel in terms of either topology or local coordination geometry around Sb3+ cations. We clarify that the statements regarding structural features of our original paper are valid in context. In reply to Krivovichev and Bindi, Deng et al. state that the structural features of their original paper are valid in context. They emphasize that this is the first time the SbO4F group has been used as a new bifunctional group to design nonlinear optical materials, and not as a structural group, and that this is the first example of a nonlinear material with a Cairo pentagonal tiling layered structure. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction (CO2ER) to multi‐carbon chemical feedstocks over Cu‐based catalysts is of considerable attraction but suffers with the ambiguous nature of active sites, which hinder the rational design of catalysts and large‐scale industrialization. This paper describes a large‐scale simulation to obtain realistic CuZn nanoparticle models and the atom‐level structure of active sites for C2+ products on CuZn catalysts in CO2ER, combining neural network based global optimization and density functional theory calculations. Upon analyzing over 2000 surface sites through high throughput tests based on NN potential, two kinds of active sites are identified, balanced Cu−Zn sites and Zn‐heavy Cu−Zn sites, both facilitating C−C coupling, which are verified by subsequent calculational and experimental investigations. This work provides a paradigm for the design of high‐performance Cu‐based catalysts and may offer a general strategy to identify accurately the atomic structures of active sites in complex catalytic systems. [ABSTRACT FROM AUTHOR]

Electrochemical redox‐control is an emerging strategy for the regulation of polymerization process without the addition of external oxidants and reductants, which enables the control over composition, microstructure and properties of the polymer products. In this paper, based on the chemical selectivity of heterometallic Salen‐Co‐Mn complexes of different valences, an electrochemically switchable strategy was developed for the copolymerization of lactide (LA), CO2 and epoxides. The switchable redox reactions endowed this system with the capability to easily synthesize a multi‐block copolymer of polylactide (PLA) and polycarbonate (PC). Moreover, the multi‐block copolymer could be further modified by introducing various monomers with different microstructures and functional groups. [ABSTRACT FROM AUTHOR]

The major challenge was to generate a bright and robust ECL signal on paper, which was solved through materials chemistry means by functionalization of the paper with a redox mediator. " I My favorite thing about my lab group is how multicultural and multidisciplinary it is.... I advise my students to try all new ideas they have and to be patient.... i " Find out more about Estela Climent in her Introducing ... Profile. Knowing about the limitations of color and fluorescence detection in such assays, we realized it with electrochemiluminescence (ECL) signaling of indicators released from (bio)gated hybrid materials. [Extracted from the article]

X‐ray photoelectron spectroscopy (XPS) is an indispensable technique in modern materials science for the determination of chemical bonding as evidenced by more than 10 000 XPS papers published annually. A literature survey reveals that in the vast majority of cases an incorrect referencing of the binding energy scale is used, neglecting warnings that have been formulated from the early days of the technique. Consequences for the data reliability are disastrous and decades of XPS work require revisiting. The purpose of this Viewpoint is to highlight the existing problems, review the criticism and suggest ways forward. [ABSTRACT FROM AUTHOR]

Herein, near‐infrared (NIR) photocontrolled iodide‐mediated reversible‐deactivation radical polymerization (RDRP) of methacrylates, without an external photocatalyst, was developed using an alkyl iodide (e.g. 2‐iodo‐2‐methylpropionitrile) as the initiator at room temperature. This example is the first use of a series of special solvents containing carbonyl groups (e.g. 1,3‐dimethyl‐2‐imidazolidinone) as both solvent and catalyst for photocontrolled RDRP using long‐wavelength (λmax=730 nm) irradiation. The polymerization system comprises monomer, alkyl iodide initiator, and solvent. Well‐defined polymers were synthesized with excellent control over the molecular weights and molecular weight distributions (Mw/Mn<1.21). The living features of this system were confirmed by polymerization kinetics, multiple controlled "on‐off" light switching cycles, and chain extension experiments. Importantly, the polymerizations proceeded successfully with various barriers (pork skin and A4 paper), demonstrating the advantage of high‐penetration NIR light. [ABSTRACT FROM AUTHOR]

We report a simple method for the photothermal welding of nonwoven mats of electrospun nanofibers by introducing a near‐infrared (NIR) dye such as indocyanine green. By leveraging the strong photothermal effect of the dye, the nanofibers can be readily welded at their cross points or even over‐welded (i.e., melted and/or fused together) to transform the porous mat into a solid film upon exposure to a NIR laser. While welding at the cross points greatly improves the mechanical strength of a nonwoven mat of nanofibers, melting and fusion of the nanofibers can be employed to fabricate a novel class of photothermal papers for laser writing or printing without chemicals or toner particles. By using a photomask, we can integrate photothermal welding with the gas foaming technique to pattern and then expand nonwoven mats into 3D scaffolds with well‐defined structures. This method can be applied to different combinations of polymers and dyes, if they can be co‐dissolved in a suitable solvent for electrospinning. [ABSTRACT FROM AUTHOR]

The article discusses the significance of citations in the publication of science research. The reasons for citing are enumerated including the tradition of scholarship, history and utility. Several guides to good citation practice are also presented including "The Modern Researcher," by Jacques Barzun and Henry Graff.

This paper describes the demonstration of a series of heterobimetallic, isoreticular 2D conductive metal–organic frameworks (MOFs) with metallophthalocyanine (MPc, M=Co and Ni) units interconnected by Cu nodes towards low‐power chemiresistive sensing of ppm levels of carbon monoxide (CO). Devices achieve a sub‐part‐per‐million (ppm) limit of detection (LOD) of 0.53 ppm toward CO at a low driving voltage of 0.1 V. MPc‐based Cu‐linked MOFs can continuously detect CO at 50 ppm, the permissible exposure limit required by the Occupational Safety and Health Administration (OSHA), for multiple exposures, and realize CO detection in air and in humid environment. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), density functional theory (DFT) calculations, and comparison experiments suggest the contribution of Cu nodes to CO binding and the essential role of MPc units in tuning and amplifying the sensing response. [ABSTRACT FROM AUTHOR]

This paper describes structural elucidation of a layered conductive metal‐organic framework (MOF) material Cu3(C6O6)2 by microcrystal electron diffraction with sub‐angstrom precision. This insight enables the first identification of an unusual π‐stacking interaction in a layered MOF material characterized by an extremely short (2.73 Å) close packing of the ligand arising from pancake bonding and ordered water clusters within pores. Band structure analysis suggests semiconductive properties of the MOF, which are likely related to the localized nature of pancake bonds and the formation of a singlet dimer of the ligand. The spin of CuII within the Kagomé arrangement dominates the paramagnetism of the MOF, leading to strong geometrical magnetic frustration. [ABSTRACT FROM AUTHOR]

Construction of a "net‐zero‐emission" system through CO2 hydrogenation to methanol with solar energy is an eco‐friendly way to mitigate the greenhouse effect. Traditional CO2 hydrogenation demands centralized mass production for cost reduction with mass water electrolysis for hydrogen supply. To achieve continuous reaction with intermittent and fluctuating flow of H2 on a small‐scale for distributed application scenarios, modulating the catalyst interface environment and chemical adsorption capacity to adapt fluctuating reaction conditions is highly desired. This paper describes a distributed clean CO2 utilization system in which the surface structure of catalysts is carefully regulated. The Ni catalyst with unsaturated electrons loaded on In2O3 can reduce the dissociation energy of H2 to overcome the slow response of intermittent H2 supply, exhibiting a faster response (12 min) than bare oxide catalysts (42 min). Moreover, the introduction of Ni enhances the sensitivity of the catalyst to hydrogen, yielding a Ni/In2O3 catalyst with a good performance at lower H2 concentrations with a 15 times adaptability for wider hydrogen fluctuation range than In2O3, greatly reducing the negative impact of unstable H2 supplies derived from renewable energies. [ABSTRACT FROM AUTHOR]

Piezochromic materials with pressure‐dependent photoluminescence tuning properties are important in many fields, such as mechanical sensors, security papers, and storage devices. Covalent organic frameworks (COFs), as an emerging class of crystalline porous materials (CPMs) with structural dynamics and tunable photophysical properties, are suitable for designing piezochromic materials, but there are few related studies. Herein, we report two dynamic three‐dimensional COFs based on aggregation‐induced emission (AIE) or aggregation‐caused quenching (ACQ) chromophores, termed JUC‐635 and JUC‐636 (JUC=Jilin University China), and for the first time, study their piezochromic behavior by diamond anvil cell technique. Due to the various luminescent groups, JUC‐635 has completely different solvatochromism and molecular aggregation behavior in the solvents. More importantly, JUC‐635 with AIE effect exhibits a sustained fluorescence upon pressure increase (≈3 GPa), and reversible sensitivity with high‐contrast emission differences (Δλem=187 nm) up to 12 GPa, superior to other CPMs reported so far. Therefore, this study will open a new gate to expand the potential applications of COFs as exceptional piezochromic materials in pressure sensing, barcoding, and signal switching. [ABSTRACT FROM AUTHOR]

Efficient bifunctional electrocatalysts for hydrogen and oxygen evolution reactions are key to water electrolysis. Herein, we report a built‐in electric field (BEF) strategy to fabricate heterogeneous nickel phosphide‐cobalt nanowire arrays grown on carbon fiber paper (Ni2P‐CoCH/CFP) with large work function difference (ΔΦ) as bifunctional electrocatalysts for overall water splitting. Impressively, Ni2P‐CoCH/CFP exhibits a remarkable catalytic activity for hydrogen and oxygen evolution reactions to obtain 10 mA cm−2, respectively. Moreover, the assembled lab‐scale electrolyzer driven by an AAA battery delivers excellent stability after 50 h electrocatalysis with a 100 % faradic efficiency. Computational calculations combining with experiments reveal the interface‐induced electric field effect facilitates asymmetrical charge distributions, thereby regulating the adsorption/desorption of the intermediates during reactions. This work offers an avenue to rationally design high‐performance heterogeneous electrocatalysts. [ABSTRACT FROM AUTHOR]

There is a constant drive for affordable point‐of‐care testing (POCT) technologies for the detection of infectious human diseases. Herein, we report a simple platform for DNA detection that takes advantage of four techniques: commercially available pregnancy test strips (PTS), amplicon generation via loop‐mediated isothermal amplification (LAMP), toehold‐mediated strand displacement, and noncovalent immobilization of DNA on paper surface with DNA nanoflowers. This simple, separation‐free platform is highly specific, as demonstrated with the detection of rtL180M, a single‐nucleotide polymorphism observed in hepatitis B virus (HBV) associated with antiviral drug resistance. It is very sensitive, capable of detecting the targeted mutation at 2 copies μL−1. It is able to correctly identify the unmutated and rtL180M genome types of HBV in clinical samples. Given its wide adaptability, we expect this platform can be easily modified for the detection of genetic variations associated with various pathogens and human diseases. [ABSTRACT FROM AUTHOR]

Force‐selective mechanochemical reactions may be important for applications in polymer mechanochemistry, yet it is difficult to achieve such reactions. This paper reports that cis‐N‐phthalimidoaziridine incorporated into a macromolecular backbone undergoes migration of N‐phthalimido group to afford imine under mechanochemical condition and not thermal one. The imine is further hydrolyzed by water bifurcating into amine and aldehyde. These structural transformations are confirmed by 1H NMR and FT‐IR spectroscopic analyses. Computational simulations are conducted for the aziridine mechanophore to propose the mechanism of reaction and define the substrate scope of reaction. [ABSTRACT FROM AUTHOR]

Hyperpolarization is a technique that can increase nuclear spin polarization with the corresponding gains in nuclear magnetic resonance (NMR) signals by 4–8 orders of magnitude. When this process is applied to biologically relevant samples, the hyperpolarized molecules can be used as exogenous magnetic resonance imaging (MRI) contrast agents. A technique called spin‐exchange optical pumping (SEOP) can be applied to hyperpolarize noble gases such as 129Xe. Techniques based on hyperpolarized 129Xe are poised to revolutionize clinical lung imaging, offering a non‐ionizing, high‐contrast alternative to computed tomography (CT) imaging and conventional proton MRI. Moreover, CT and conventional proton MRI report on lung tissue structure but provide little functional information. On the other hand, when a subject breathes hyperpolarized 129Xe gas, functional lung images reporting on lung ventilation, perfusion and diffusion with 3D readout can be obtained in seconds. In this Review, the physics of SEOP is discussed and the different production modalities are explained in the context of their clinical application. We also briefly compare SEOP to other hyperpolarization methods and conclude this paper with the outlook for biomedical applications of hyperpolarized 129Xe to lung imaging and beyond. [ABSTRACT FROM AUTHOR]

As a typical class of man‐made nanoreactors, metal‐loaded hollow carbon nanostructures (MHC nanoreactors) exhibit competitive potentials in the heterogeneous catalysis due to their tailorable microenvironment effects, in which the void‐confinement effect is one of the most fundamental functions in boosting the catalytic performance. Herein this paper, Ru‐loaded hollow carbon spheres are employed as nanoreactors with a crucial biomass hydrogenation process, levulinic acid (LA) hydrogenation into γ‐valerolactone, as the probe reaction to further recognize the forming mechanism of this pivotal effect. We demonstrated that the void‐confinement effect of the selected MHC nanoreactors is essentially driven by an integrating action of electronic metal‐support interaction, reactant enrichment and diffusion, which are mainly ascribed to peculiar properties of hollow nanoreactors both in electronic and structural aspects, respectively. This work offers a distinct case for interpreting the catalytic behaviour of MHC nanoreactors, which could potentially promise broader insights into the microenvironment engineering strategies of hollow nanostructures. [ABSTRACT FROM AUTHOR]

An interview with Gautam R. Desiraju, a professor at the Indian Institute of Science in Bangalore, India, is presented. When asked about the state of chemistry research, he stated that the evolution is not with chemistry but with the way research is being conducted. He expressed his views on the quality of chemistry studies. He also mentioned that his favorite painter is Diego Velasquez.

Metal–organic frameworks (MOFs) enable the design of host–guest systems with specific properties. In this work, we show how the confinement of anthracene in a well‐chosen MOF host leads to reversible yellow‐to‐purple photoswitching of the fluorescence emission. This behavior has not been observed before for anthracene, either in pure form or adsorbed in other porous hosts. The photoresponse of the host–guest system is caused by the photodimerization of anthracene, which is greatly facilitated by the pore geometry, connectivity, and volume as well as the structural flexibility of the MOF host. The photoswitching behavior was used to fabricate photopatternable and erasable surfaces that, in combination with data encryption and decryption, hold promise in product authentication and secure communication applications. The confinement of anthracene molecules in a metal–organic framework enables reversible yellow‐to‐purple photoswitching of the fluorescence emission. The photoresponse of the host–guest system strongly relies on the unique properties of the MOF host, that is, the pore geometry, connectivity, and volume as well as the structural flexibility. The solid‐state photoswitching enabled the development of photopatternable, erasable, and rewritable paper. [ABSTRACT FROM AUTHOR]

Oxidative polymerization of nickel(II) 5,15‐diphenyl porphyrin and nickel(II) 5,15‐bis(di‐3,5‐tert‐butylphenyl) porphyrin by oxidative chemical vapor deposition (oCVD) yields multiply fused porphyrin oligomers in thin film form. The oCVD technique enables one‐step formation, deposition, and p‐doping of conjugated poly(porphyrins) coatings without solvents or post‐treatments. The decisive reactions and side reactions during the oCVD process are shown by high‐resolution mass spectrometry. Owing to the highly conjugated structure of the fused tapes, the thin films exhibit an electrical conductivity of 3.6×10−2 S cm−1 and strong absorption in the visible to near‐infrared spectral region. The formation of smooth conjugated poly(porphyrins) coatings, even on sensitive substrates, is demonstrated by deposition and patterning on glass, silicon, and paper. Formation of conductive poly(porphyrins) thin films could enable the design of new optoelectronic devices using the oCVD approach. Directly fused metalloporphyrin tapes were simultaneously synthesized and deposited in a thin film form by scalable and substrate‐independent chemical vapor deposition (CVD). Patterned and conductive (3.6×10−2 S cm−1) conjugated poly(porphyrin) thin films are formed. Mass spectrometry provides insight into the oxidative polymerization reaction and two side reactions (metalloporphyrin chlorination and π extension via intramolecular ring fusion). [ABSTRACT FROM AUTHOR]

Selected current trends in analytical chemistry are discussed and traced back to original work published more than a hundred years ago in the same field. Gravimetric microanalysis has been transformed into a mass‐sensitive sensor technology. New developments in molecular spectroscopy are seen in Raman spectroscopy. In the area of chemical sensors, paper‐based devices with visual readout (dipsticks, microfluidic pads) celebrate a revival. In "green" applications, the separation of analytes from complicated matrices is often the key to successful analysis. Continuous separation techniques are essential for the 24/7 production of goods with certified quality. Finally, micro‐ and nanoscale techniques rely on highly selective receptors, and their development is based on detailed understanding of the structure of ligand–receptor complexes. Back to the future: Selected current developments in analytical chemistry are discussed in this Viewpoint and traced back to original work published up to 150 years ago. Discussed topics include selective mass determination, molecular spectroscopy, chemical sensors, separation methods, and bioinspired receptors such as antibodies. [ABSTRACT FROM AUTHOR]

Stimuli-responsive photoluminescent (PL) materials have been widely used as fluorescent ink for data security applications. However, traditional fluorescent inks are limited in maintaining the secrecy of information because the inks are usually visible by naked eyes either under ambient light or UV-light illumination. Here, we introduced metal-free water-soluble graphitic carbon nitride quantum dots (g-CNQDs) as invisible security ink for information coding, encryption, and decryption. The information written by the g-CNQDs is invisible in ambient light and UV light, but it can be readable by a fluorescence microplate reader. Moreover, the information can be encrypted and decrypted by using oxalic acid and sodium bicarbonate as encryption reagent and decryption reagent, respectively. Our findings provide new opportunities for high-level information coding and protection by using water-soluble g-CNQDs as invisible security ink. [ABSTRACT FROM AUTHOR]

The conversion of biomass into valuable carbon composites as efficient non-precious metal oxygen-reduction electrocatalysts is attractive for the development of commercially viable polymer electrolyte membrane fuel-cell technology. Herein, a versatile iron-tannin-framework ink coating strategy is developed to fabricate cellulose-derived Fe3C/Fe-N-C catalysts using commercial filter paper, tissue, or cotton as a carbon source, an iron-tannin framework as an iron source, and dicyandiamide as a nitrogen source. The oxygen reduction performance of the resultant Fe3C/Fe-N-C catalysts shows a high onset potential (i.e. 0.98 V vs the reversible hydrogen electrode (RHE)), and large kinetic current density normalized to both geometric electrode area and mass of catalysts (6.4 mA cm−2 and 32 mA mg−1 at 0.80 V vs RHE) in alkaline condition. This method can even be used to prepare efficient catalysts using waste carbon sources, such as used polyurethane foam. [ABSTRACT FROM AUTHOR]

Thick, uniform, easily processed, highly conductive polymer films are desirable as electrodes for solar cells as well as polymer capacitors. Here, a novel scalable strategy is developed to prepare highly conductive thick poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (HCT-PEDOT:PSS) films with layered structure that display a conductivity of 1400 S cm−1 and a low sheet resistance of 0.59 ohm sq−1. Organic solar cells with laminated HCT-PEDOT:PSS exhibit a performance comparable to the reference devices with vacuum-deposited Ag top electrodes. More importantly, the HCT-PEDOT:PSS film delivers a specific capacitance of 120 F g−1 at a current density of 0.4 A g−1. All-solid-state flexible symmetric supercapacitors with the HCT-PEDOT:PSS films display a high volumetric energy density of 6.80 mWh cm−3 at a power density of 100 mW cm−3 and 3.15 mWh cm−3 at a very high power density of 16160 mW cm−3 that outperforms previous reported solid-state supercapacitors based on PEDOT materials. [ABSTRACT FROM AUTHOR]

Medication adherence is a medical and societal issue worldwide, with approximately half of patients failing to adhere to prescribed treatments. The goal of this Minireview is to examine how recent work on microfluidics for point‐of‐care diagnostics may be used to enhance adherence to medication. It specifically focuses on capillary microfluidics since these devices are self‐powered, easy to use, and well established for diagnostics and drug monitoring. Considering that an improvement in medication adherence can have a much larger effect than the development of new medical treatments, it is long overdue for the research communities working in chemistry, biology, pharmacology, and material sciences to consider developing technologies to enhance medication adherence. For these reasons, this Minireview is not meant to be exhaustive but rather to provide a quick starting point for researchers interested in joining this complex but intriguing and exciting field of research. [ABSTRACT FROM AUTHOR]

Cu‐based electrocatalysts facilitate CO2 electrochemical reduction (CO2ER) to produce multi‐carbon products. However, the roles of Cu0 and Cu+ and the mechanistic understanding remain elusive. This paper describes the controllable construction of Cu0‐Cu+ sites derived from the well‐dispersed cupric oxide particles supported on copper phyllosilicate lamella to enhance CO2ER performance. 20 % Cu/CuSiO3 shows the superior CO2ER performance with 51.8 % C2H4 Faraday efficiency at −1.1 V vs reversible hydrogen electrode during the 6 hour test. In situ attenuated total reflection infrared spectra and density functional theory (DFT) calculations were employed to elucidate the reaction mechanism. The enhancement in CO2ER activity is mainly attributed to the synergism of Cu0‐Cu+ pairs: Cu0 activates CO2 and facilitates the following electron transfers; Cu+ strengthens *CO adsorption to further boost C−C coupling. We provide a strategy to rationally design Cu‐based catalysts with viable valence states to boost CO2ER. [ABSTRACT FROM AUTHOR]

Molecules in confined spaces exhibit unusual behaviors that are not typically observed in bulk systems. Such behavior can provide alternative strategies for exploring new reaction pathways. Cleavage of the C=N bond of Nile red (NR) in solution is an irreversible reaction. Here, we used spatial confinement within a cationic micelle‐confined system to convert this reaction to a reversible process. The fluorescence of NR shifted between red and green for nine cycles. The new chemical pathway based on spatial confinement can be attributed to two factors: increasing the local concentration of reactants and reducing the reaction energy barrier. This effect is supported by both experimental evidence and theoretical calculations. The cross‐linked silica shell comprising the confinement chamber stabilizes the enclosed molecules. This reduces fluorophore leakage and maintains fluorescence intensity in most environments, including in solution, on paper, and in hydrogel films, and expands practical applications in encrypted information and multi‐informational displays. [ABSTRACT FROM AUTHOR]

Crystallography modulation of zinc (Zn) metal anode is promising to promote Zn reversibility in aqueous electrolytes, but efficiently constructing Zn with specific crystallographic texture remains challenging. Herein, we report a current‐controlled electrodeposition strategy to texture the Zn electrodeposits in conventional aqueous electrolytes. Using the electrolytic cell with low‐cost Zn(CH3COO)2 electrolyte and Cu substrate as a model system, the texture of as‐deposited Zn gradually transforms from (101) to (002) crystal plane as increasing the current density from 20 to 80 mA cm−2. Moreover, the high current accelerates the Zn nucleation rate with abundant nuclei, enabling uniform deposition. The (002) texture permits stronger resistance to dendrite growth and interfacial side reactions than the (101) texture. The resultant (002)‐textured Zn electrode achieves deep cycling stability and supports the stable operation of full batteries with conventional V/Mn‐based oxide cathodes. [ABSTRACT FROM AUTHOR]

This paper describes a new method for the transannular functionalization of the γ‐C−H bonds in alicyclic amines to install C(sp3)−halogen, oxygen, nitrogen, boron, and sulfur bonds. The key challenge for this transformation is controlling the relative rate of Cγ−H versus Cα−H functionalization. We demonstrate that this selectivity can be achieved by pre‐complexation of the substrate with Pd prior to the addition of oxidant. This approach enables the use of diverse oxidants that ultimately install various heteroatom functional groups at the γ‐position with high site‐ and diastereoselectivity. [ABSTRACT FROM AUTHOR]

The design of catalysts with high activity, selectivity, and stability is key to the electroreduction of CO2. Herein, we report the synthesis of 3D hierarchical metal/polymer–carbon paper (M/polymer‐CP) electrodes by in situ electrosynthesis. The 3D polymer layer on CP (polymer‐CP) was first prepared by in situ electropolymerization, then a 3D metal layer was decorated on the polymer‐CP to produce the M/polymer‐CP electrode. Electrodes with different metals (e.g. Cu, Pd, Zn, Sn) and various polymers could be prepared by this method. The electrodes could efficiently reduce CO2 to desired products, such as C2H4, CO, and HCOOH, depending on the metal used. For example, C2H4 could be formed with a Faradaic efficiency of 59.4 % and a current density of 30.2 mA cm−2 by using a very stable Cu/PANI‐CP electrode in an H‐type cell. Control experiments and theoretical calculations showed that the 3D hierarchical structure of the metals and in situ formation of the electrodes are critical for the excellent performance. [ABSTRACT FROM AUTHOR]

Polymerization sites of small molecule acceptors (SMAs) play vital roles in determining device performance of all‐polymer solar cells (all‐PSCs). Different from our recent work about fluoro‐ and bromo‐ co‐modified end group of IC‐FBr (a mixture of IC‐FBr1 and IC‐FBr2), in this paper, we synthesized and purified two regiospecific fluoro‐ and bromo‐ substituted end groups (IC‐FBr‐o & IC‐FBr‐m), which were then employed to construct two regio‐regular polymer acceptors named PYF‐T‐o and PYF‐T‐m, respectively. In comparison with its isomeric counterparts named PYF‐T‐m with different conjugated coupling sites, PYF‐T‐o exhibits stronger and bathochromic absorption to achieve better photon harvesting. Meanwhile, PYF‐T‐o adopts more ordered inter‐chain packing and suitable phase separation after blending with the donor polymer PM6, which resulted in suppressed charge recombination and efficient charge transport. Strikingly, we observed a dramatic performance difference between the two isomeric polymer acceptors PYF‐T‐o and PYF‐T‐m. While devices based on PM6:PYF‐T‐o can yield power conversion efficiency (PCE) of 15.2 %, devices based on PM6:PYF‐T‐m only show poor efficiencies of 1.4 %. This work demonstrates the success of configuration‐unique fluorinated end groups in designing high‐performance regular polymer acceptors, which provides guidelines towards developing all‐PSCs with better efficiencies. [ABSTRACT FROM AUTHOR]

Polyalkyl furans are widespread in nature, often performing important biological roles. Despite a plethora of methods for the synthesis of tetrasubstituted furans, the construction of tetraalkyl furans remains non‐trivial. The prevalence of alkyl groups in bioactive furan natural products, combined with the desirable bioactivities of tetraalkyl furans, calls for a general synthetic protocol for polyalkyl furans. This paper describes a Michael–Heck approach, using sequential phosphine‐palladium catalysis, for the preparation of various polyalkyl furans from readily available precursors. The versatility of this method is illustrated by the total syntheses of nine distinct polyalkylated furan natural products belonging to different classes, namely the furanoterpenes rosefuran, sesquirosefuran, and mikanifuran; the marine natural products plakorsins A, B, and D and plakorsin D methyl ester; and the furan fatty acids 3D5 and hydromumiamicin. [ABSTRACT FROM AUTHOR]

Here we show that by adjusting the concentration of tetrabutyl ammonium and phosphonium salts in water (≈1.5–2.0 m), hydrophobic solvation triggers the formation of a unique, highly incompressible supramolecular liquid, with a dynamic structure similar to clathrates, involving essentially all H2O molecules of the solvent. Despite the increasing local order, the thermal diffusivity, and compressibility of these supramolecular liquids is strongly decreased with respect to bulk water due to slower relaxation dynamics. The results presented in this paper open an avenue to design a new family of supramolecular fluids, stable under atmospheric conditions, which can find important technological applications in energy storage and conversion. [ABSTRACT FROM AUTHOR]

In the study of structure–property relationships for rational materials design, hollow multishell structures (HoMSs) have attracted tremendous attention owing to the optimal balance between mass transfer and surface exposure. Considering the shell structure can significantly affect the properties of HoMSs, in this paper, we provide a novel one‐step strategy to continually regulate the shell structures of HoMSs. Through a simple phosphorization process, we can effectively modify the shell from solid to bubble‐like and even duplicate the shells with a narrow spacing. Benefitting from the structure merits, the fabricated CoP HoMSs with close duplicated shells can promote gas release owing to the unbalanced Laplace pressure, while accelerating liquid transfer for enhanced capillary force. It can provide effective channels for water and gas and thus exhibits a superior electrocatalytic performance in the hydrogen and oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

The paper reports formation of exceptionally large capsular species (diameter of c. a. 30 Å) by interactions of polyphenolic macrocycles with 5‐fold symmetry with anions. Pyrogallol[5]arenes and resorcin[5]arenes interact with anions via hydrogen bonds involving phenolic OH groups or aromatic CH groups. Based on NMR titration experiments, diffusion coefficients, and geometric requirements, it is postulated that the capsules have (P5H)12(X−)60 or (R5H)12(X−)60 stoichiometry and a unique geometry of one of the Platonic solids—a dodecahedron. The capsules exist in THF and in benzene, but not in chloroform, reflecting competitive effects in the solvation of anions. It is also demonstrated that mechanochemical pre‐treatment (dry‐milling) of solid samples is indispensable to initialize self‐assembly in benzene. [ABSTRACT FROM AUTHOR]

Vladimir Vasil′evich Markovnikov (1837–1904) was a Russian chemist whose graduate research at Kazan Imperial University from 1860–1869 gave us, among other things, one of the most enduring empirical rules in organic chemistry. Markovnikov's Rule for electrophilic addition was first published in the inaugural volume of the Journal of the Russian Chemical Society (Zh. Russ. Khim. O‐va.), but it was not until a year later when it was published in German that it received attention internationally. The rule itself was worded differently from the most common modern versions, in that it is expressed in terms of the electronegative part of the adding reagent. It has been suggested that this rule was the result of an inspired guess, but a careful examination of Markovnikov's graduate dissertations reveals a very different picture. In the dissertations, there is a careful build‐up of logic from which the rule itself, as defined by Markovnikov, emerges naturally. Markovnikov's Rule was most decidedly not an inspired guess. [ABSTRACT FROM AUTHOR]

Silicon is a promising photocathode material in photoelectrochemical water splitting for hydrogen production, but it is primarily limited by photocorrosion in aqueous electrolytes. As an extensively used protective material, crystalline TiO2 could protect Si photoelectrode against corrosion. However, a large number of grain boundaries (GBs) in polycrystalline TiO2 would induce excessive recombination centers, impeding the carrier transport. This paper describes the introduction of oxygen vacancies (Ovac) with controllable spatial distribution for GBs to promote carrier transport. Two kinds of Ovac distribution, Ovac along GBs and Ovac inside grains, are compared, where the latter one is demonstrated to facilitate carrier transport owing to the formation of tunneling paths across GBs. Consequently, a simple p‐Si/TiO2/Pt heterojunction photocathode with controllable Ovac distribution in TiO2 shows a +400 mV onset potential shift and yields an applied bias photon‐to‐current efficiency of 5.9 %, which is the best efficiency reported among silicon photocathodes except for silicon homojunction. [ABSTRACT FROM AUTHOR]

Nucleophilic substitutions, including SN1 and SN2, are classical and reliable reactions, but a serious drawback is their intolerance for both bulky nucleophiles and chiral tertiary alkyl electrophiles for the synthesis of a chiral quaternary carbon center. An SRN1 reaction via a radical species is another conventional method used to carry out substitution reactions of bulky nucleophiles and alkyl halides, but chiral tertiary alkyl electrophiles cannot be used. Therefore, a stereospecific nucleophilic substitution reaction using chiral tertiary alkyl electrophiles and bulky nucleophiles has not yet been well studied. In this paper, we describe the reaction of tertiary alkyl alcohols and non‐chiral or chiral α‐bromocarboxamides as a tertiary alkyl source for the formation of congested ether compounds possessing two different tertiary alkyl groups on the oxygen atom with stereoretention. [ABSTRACT FROM AUTHOR]

The development of lead‐free perovskite photoelectric materials has been an extensive focus in the recent years. Herein, a novel one‐dimensional (1D) lead‐free CsMnCl3(H2O)2 single crystal is reported with solvatochromic photoluminescence properties. Interestingly, after contact with N,N‐dimethylacetamide (DMAC) or N,N‐dimethylformamide (DMF), the crystal structure can transform from 1D CsMnCl3(H2O)2 to 0D Cs3MnCl5 and finally transform into 0D Cs2MnCl4(H2O)2. The solvent‐induced crystal‐to‐crystal phase transformations are accompanied by loss and regaining of water of crystallization, leading to the change of the coordination number of Mn2+. Correspondingly, the luminescence changes from red to bright green and finally back to red emission. By fabricating a test‐paper containing CsMnCl3(H2O)2, DMAC and DMF can be detected quickly with a response time of less than one minute. These results can expand potential applications for low‐dimensional lead‐free perovskites. [ABSTRACT FROM AUTHOR]

Proximal noncovalent forces are commonplace in natural systems and understanding the consequences of their juxtaposition is critical. This paper experimentally quantifies for the first time a Hydrogen Bond‐Enhanced Halogen Bond (HBeXB) without the complexities of protein structure or preorganization. An HBeXB is a halogen bond that has been strengthened when the halogen donor simultaneously accepts a hydrogen bond. Our theoretical studies suggest that electron‐rich halogen bond donors are strengthened most by an adjacent hydrogen bond. Furthermore, stronger hydrogen bond donors enhance the halogen bond the most. X‐ray crystal structures of halide complexes (X−=Br−, I−) reveal that HBeXBs produce shorter halogen bonds than non‐hydrogen bond analogues. 19F NMR titrations with chloride highlight that the HBeXB analogue exhibits stronger binding. Together, these results form the foundation for future studies concerning hydrogen bonds and halogen bonds in close proximity. [ABSTRACT FROM AUTHOR]

Deep understanding of structure–property relationship between packing of chiral building units and their chiroptical behaviors would significantly facilitate the rational design and fabrication of the emerging chiroptical materials such as circularly polarized luminescence (CPL) emissive materials. In this paper, we unveil the universal existence of supramolecular tilt helical superstructures in self‐assembled π‐conjugated amino acid derivatives. A series of coded amino acid methyl esters were conjugated to anthracene segments at N‐terminus, which afforded 21 and 31 symmetry supramolecular tilt chirality in solid‐states. Helical assemblies enabled diversified Cotton effects and CPL performances, which were in accordance with the tilted chirality between anthracene segments. Such correlation shows fine universality, whereby the chiroptical prediction could be realized. Furthermore, on top of charge‐transfer complexation, manipulation of CPL emission colors and handedness were realized. [ABSTRACT FROM AUTHOR]

Hybrid perovskite (HP) materials are of interest in photovoltaics and lighting applications. Here we report that hybrid perovskite composites, as crystallized powders, can behave as intelligent materials showing highly sensitive and reversible mechanochromic luminescence (MCL). Composites consisting of monolayered 2D HP and 3D HP components exhibit reversible tunable color emission upon mechanical strain. The bluish‐whitish emission of the 2D HP turns into orange in the composite owing to an energy transfer process. The bright green emission, observed as soon as the composite is slightly crushed, originates from the 3D HP after efficient energy funneling from the multi‐layered 2D HP produced at the 2D/3D interface by the mechanical treatment. Besides highlighting the key role of the interfaces in light emission of HP, our findings pave the way for hybrid perovskites as highly sensitive MCL smart materials for mechanosensors, security papers, or optical storage applications. [ABSTRACT FROM AUTHOR]

The invasion of cancer is brought about by continuous interaction of malignant cells with their surrounding tissue microenvironment. Investigating the remodeling of local extracellular matrix (ECM) by invading cells can thus provide fundamental insights into the dynamics of cancer progression. In this paper, we use an active untethered nanomechanical tool, realized as magnetically driven nanomotors, to locally probe a 3D tissue culture environment. We observed that nanomotors preferentially adhere to the cancer‐proximal ECM and magnitude of the adhesive force increased with cell lines of higher metastatic ability. We experimentally confirmed that sialic acid linkage specific to cancer‐secreted ECM makes it differently charged, which causes this adhesion. In an assay consisting of both cancerous and non‐cancerous epithelia, that mimics the in vivo histopathological milieu of a malignant breast tumor, we find that nanomotors preferentially decorate the region around the cancer cells. [ABSTRACT FROM AUTHOR]