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Fluorenes are employed to lock biphenyl groups in triarylamine units. Such a novel donor block brings about numerous advantages, enabling a thermally activated delayed fluorescence emitter with state-of-the-art deep-red/NIR efficiencies in OLEDs.

Galactosylated chitosan-coated liposome improved the therapeutic efficacy of oleanolic acid for the treatment of hepatocellular carcinoma through hepatocyte-targeted delivery, as demonstrated by using an axillary tumor xenograft mouse model.

A new degradation mechanism of ionomer decomposition in catalyst layers was directly monitored by 19F NMR spectrum analysis.

Herein we present a diastereoselective addition of arylboronic acids to α-keto N-tert-butanesulfinyl aldimines catalyzed by a Rh(i) catalyst.

Binder-free Ni modified-MoS2 electrocatalysts with superior hydrogen evolution reaction (HER) catalytic performance were fabricated by a facile electrodeposition method.

A practical method can be used to assemble four simple molecules into an aromatic system, by which m-alkenyl benzaldehydes can be synthesized with regiospecificity. Moreover, new AIE molecules can be obtained by coupling the products in one pot.

Freezing-induced hydrate formation from MgCl2 aqueous solution was monitored using terahertz time-domain spectroscopy.

Regioselective cyanoalkylalkenylation of 3-aza-1,5-dienes with oxime esters induced by visible light.

By introducing multiple molecule/intermolecular hydrogen bonds into the polydimethylsiloxane elastomer system, the solid polymeric electrolyte with high ion conductivity and high electrochemical stability obtains the fast self-healing speed.

Transition-metal sulfides (MxSy) have attracted great interest as promising catalysts for the hydrogen evolution reaction (HER) due to their low cost. However, the formation of sulfur–hydrogen bonds on MxSy (S–Hads) severely suppresses the HER. In this paper, we report a three-dimensional nickel sulfide (Ni3S2) film supported by Ag nanorods (NRs) on Ni foam (Ni3S2–Ag/NF) as a type of electrocatalyst for the HER in alkaline media. The tight coupling between Ag and Ni3S2 creates a mass of heterojunctions. Therefore, this electrocatalyst only shows a low overpotential of 161 mV at 10 mA cm−2, as well as satisfactory stability for 10 h. Density functional theory calculations reveal that the intense electronic interactions in the heterojunctions of the Ni3S2–Ag hybrids can facilitate water adsorption and activation, improve H-adsorption and desorption on the electrocatalysts, and reduce the formation of S–Hads bonds on the catalyst surfaces. The existence of strong interactions between Ag and Ni3S2 in the electrocatalyst can facilitate both the Volmer and Heyrovsky steps of the HER and cause the Ni3S2–Ag/NF electrocatalysts to exhibit outstanding HER catalytic performance. This suitable strategy involving Ag doping may be a promising choice for developing Ni sulfide-based electrocatalysts for the HER.

Artificial synapses are memristor-based devices mimicking biological synapses, and they are used in neuromorphic computing systems that process information in a parallel, energy efficient way and store information in an analog, non-volatile form. The next generation of computing systems are anticipated to use memristive circuits, as they can overcome the shortcomings of the von Neumann computer architecture in which the levels of memory and the CPU are separated, creating a bottleneck that causes energy-loss during information transfer. Memristors are utilized to build Resistive Random Access Memory (RRAM) that allows for multi-level data storage and construction of self-correcting, autonomous learning systems that can solve complex computational tasks that have historically required super-computing hardware. Artificial synapses have received attention since HP Labs fabricated the first practical memristor device. In this review we summarize the working principles, device architectures, fabrication and processing techniques, as well as the strategies for materials selection including binary metal oxide, perovskite, polymer, and organic materials. We also discuss the applications and challenges of using artificial synapses in artificial intelligence tasks such as image recognition, tactile sensing and speech recognition.

Gas–liquid discharge non-thermal plasma (NTP) coupled with an ozonation reactor was used to investigate the removal of a broad-spectrum antibacterial agent, chloroxylenol (PCMX), from aqueous solution. Under the same experimental conditions (discharge power of 50.25 W, the initial concentration of PCMX of 60 mg L−1, oxygen flow of 1.0 L min−1 and PCMX solution flow of 150 mL min−1), the PCMX degradation rates in the ozonation-only, NTP-only and NTP/O3 systems were 29.25%, 67.04% and 79.43%, respectively. Correspondingly, the energy efficiency has also been greatly improved, and increased to 0.45, 1.03 and 1.21 g kW−1 h−1. In addition, the effects of the initial concentration of PCMX, initial pH, the flow rate of oxygen, the addition of H2O2 and the addition of a radical scavenger on the degradation rate of PCMX were investigated in the NTP/O3 system. The degradation rate in acidic solutions was higher than that in alkaline solutions. During the removal process of PCMX, the rate of degradation was strongly increased with the addition of H2O2 and acutely decreased with the addition of the radical scavenger. Compared with deionized water the degradation rates of PCMX in secondary effluent were inhibited. Four main intermediates of PCMX degradation by the NTP/O3 system were identified by gas chromatography-mass spectrometry (GC-MS) and a possible degradation pathway of PCMX was proposed. The changes in toxicity of the PCMX solution during the NTP/O3 system oxidation process were also evaluated using bioluminescent bacteria and Quantitative Structure Activity Relationship (QSAR) models with the help of the ECOSAR software.

We have developed a mild catalytic approach for the synthesis of new dithienofuran derivatives via cascade copper catalysed dual C–S coupling and subsequent ring closure reactions. Sonogashira coupling between perbromofuran and terminal alkynes produced 3,4-dibromo-2,5-dialkynylfuran (1) in good yields. Next, copper catalysed C–S coupling between 1 and Na2S·9H2O and a subsequent ring-closure reaction afforded dithienofuran compounds (2) under mild conditions. We found that this strategy shows broad substrate scope and can be used to prepare not only aryl and heteroaryl but also alkyl substituted dithienofuran derivatives in up to 70% yields. Furthermore, we proposed a mechanism including two catalytic cycles: a typical Cu(I)/Cu(III) catalytic cycle and a subsequent Cu(II) induced cyclization mechanism.

In situ electrochemical activation as a new pretreating method to adjust electrocatalytic performance attracts extensive attention. However, the activation mechanisms of electrocatalysts are still ambiguous. Herein, we propose a facile modulation strategy of in situ cathodic activation of FePx based on W-incorporation (W-FePx/IF) for the hydrogen evolution reaction (HER). The activated W-FeOx with obvious surface reconstruction demonstrates the role of W-incorporation for driving the cathodic activation of FePx, which suggests the larger surface area and more active sites. In fact, W incorporation can not only accelerate the cathodic activation process but also act as the adsorption sites for Had to form the synergistic effect with FeOx for water dissociation. The obtained W-FeOx/IF exhibits greatly enhanced HER activity featuring decreased overpotential from 237.7 to 154.0 mV at 100 mA cm−2, which may be ascribed to W-FeOx with double catalytic active sites after cathodic activation. Additionally, the modulation effects of cathodic activation can be exactly achieved by changing electrochemical parameters such as CV cycles. W-FeOx/IF also shows excellent long-term stability for at least 100 h at 100 mA cm−2. This modulation engineering based on metal doping is expected to provide inspiration for the understanding of the cathodic activation process for efficient electrocatalysts.

The cooling-induced formation of a hydrate in aqueous NaCl solutions was probed using terahertz time-domain spectroscopy (THz-TDS). It was found that the NaCl hydrate formation is accompanied by the emergence of four new absorption peaks at 1.60, 2.43, 3.34 and 3.78 THz. Combining X-ray diffraction measurements with solid-state based density functional theory (DFT) calculations, we assign the observed terahertz absorption peaks to the vibrational modes of the formed NaCl·2H2O hydrate during cooling. This work shows that THz-TDS based analysis has great potential in studying ionic hydrates and the newly revealed collective vibrational modes could be sensitive indicators to achieve quantitative analysis in phase transitions and lattice dynamics.

In order to improve drug efficacy, and reduce drug toxicity and side effects, a novel drug controlled release system was developed based on mesoporous silica nanoparticles (MSNs) with gold nanoparticles (AuNPs) acting as pore caps and short single-stranded DNA (ssDNA) oligomers as the linker. The synthesised composites were characterized by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), thermogravimetric analysis (TGA), zeta potential measurement, transmission electron microscopy (TEM) and UV-vis spectroscopy. The anticancer drug doxorubicin (Dox) was applied as a model drug to investigate the 808 nm near infrared (NIR) laser-controlled drug release behavior at different pH by fluorescence measurements. The investigation results demonstrate that this nanocarrier could achieve drug controlled release by external near-infrared (NIR) laser stimulation, which is expected to be applied in cancer therapy.

We describe a nickel-catalyzed highly regio- and stereoselective migratory fluoro-alkenylation of unactivated alkyl bromides. A unique catalytic cycle merging alkyl nickel chain-walking and defluorinative coupling enables the introduction of a broad array of fluoroalkenyl moieties into carbon chains. Control experiments with other halogenated alkenes demonstrated the essential role of fluorine atoms in this reaction. Notably, the reaction proceeds under mild conditions and allows for the synthesis of a variety of valuable monofluoroalkenes.

The catalytic C–F bond carboxylation of organofluorines with CO2 gas remains a challenging problem in synthetic chemistry. Here, we describe a selective defluorinative carboxylation of gem-difluoroalkenes through photoredox/palladium dual catalysis. The C–F bond activation is enabled by single electron reduction through photoredox catalysis to generate a fluorovinyl radical, which subsequently participates in an unprecedented palladium-catalyzed carboxylation. This novel C–F functionalization proved applicable to a wide range of substituted gem-difluoroalkenes, providing a rapid access to valuable α-fluoroacrylic acids.

Herein we demonstrate that an alkylation of indoles could be accessed through C-H bond functionalization with α,α-difluorovinyl tosylate. The key aspect for the effective alkylation is the influence of the fluorine substituents on the reactivity of the C[double bond, length as m-dash]C double bond, allowing regioselective insertion as well as an indolyl group shift process. Furthermore, the fluorides are removed through alcoholysis to furnish the alkylation product as a traceless auxiliary.

Sacubitril–valsartan (SV) is a first-in-class inhibitor of the angiotensin II receptor and neprilysin for the treatment of chronic heart failure (HF) and hypertension. A stereoselective normal-phase high performance liquid chromatographic method was developed and validated for separation of sacubitril (SA), valsartan (VA) and their stereoisomeric impurities. Chromatography was performed using mobile phase A of n-hexane with 0.1% TFA added and mobile phase B comprising ethanol, isopropanol and TFA (80 : 20 : 0.1, v/v/v) and delivered at a flow rate of 1.0 mL min−1 on a Chiralcel OJ-H column (250 mm × 4.6 mm, 5 μm). The stereoisomers were monitored at a wavelength of 254 nm and the whole separation was achieved within 50 min. The method was validated in terms of specificity, linearity (R2 ≥ 0.998), accuracy (98.3–99.5%), precision (%RSD ≤ 1.82), limit of detection (0.06 μg mL−1 and 0.10 μg mL−1) and limit of quantification (0.2 μg mL−1 and 0.3 μg mL−1). The sample solution and mobile phase were found to be stable for at least 48 hours. The final optimized method was successfully applied to separate sacubitril–valsartan from their stereoisomers and showed characteristics of good repeatability and accuracy for quantitative determination of the stereoisomers in bulk drug.

A collaborative strategy is developed for constructing stable lithium metal anodes by using self-supporting three-dimensional nitrogen-doped graphene foams as the multifunctional host matrix. The resultant electrode shows impressive electrochemical performances, attributable to the three-dimensional porous architecture and nitrogen-doping nature of such a unique host matrix.

A novel set of amphiphilic conjugated molecules consisting of highly emissive fluorene and pyrene species functionalized with phosphonate polar pendant groups, namely PEP and POEP, were designed and synthesized. The novel molecular design endows the resulting molecules with good solution processability, excellent thermal stability, and multifunctional optoelectronic properties, i.e. bright blue emission in films and efficient interfacial functionality, which contribute to effectively lowering the electron injection barriers for efficient electron injection from the cathode. As a result, by using the multifunctional amphiphilic conjugated molecules as both light emitters and cathode interlayers, inkjet-printed single-layer organic light-emitting diodes (OLEDs) with an ITO/PEDOT:PSS/PEP or POEP/Al configuration have been successfully constructed. Comparable or even superior device characteristics have been achieved in comparison with those of spin-cast devices. In particular, inkjet printed devices based on PEP exhibited a low turn-on voltage (Von) of 3.8 V, a maximum current efficiency (ηc,max) of 1.12 cd A−1 at 10.0 V (687.2 mA cm−2), and a high maximum brightness (Lmax) of 8850.1 cd m−2 at 11.0 V. According to these results, such a novel molecular design is beneficial for achieving high-performance inkjet-printed OLEDs with simplified device architecture, which can help in tackling the hurdle of conventional multilayer devices with high work-function electrodes.

A monodispersed 15 nm Ni9Pt1 catalyst synthesized via a reverse microemulsion method, shows a lower activation energy than both Ni and Pt catalysts during the methane cracking reaction. Thanks to the synergic effect of Ni–Pt alloy, this catalyst presents a stable H2 formation rate at 700 °C, and forms carbon nanotubes, anchoring the catalyst particles on top.

This work reports on the self-assemblies of amphiphilic biodegradable cholesterol-containing block copolymers PEG-b-PMCC. The polymers are prepared through the ring opening polymerization (ROP) of a methyl and cholesteryl substituted trimethylenecarbonate monomer (MCC). They can self-assemble into smectic ellipsoidal vesicles in water through the transition from smectic nanofibers.

An unprecedented Rh-catalyzed C2-difluoroalkylation of indole derivatives with 2,2-difluorovinyl arenesulfonates has been reported. This reaction provides a rare instance of catalytic difluoroalkylation through hydroarylation of gem-difluoroalkenes. The sulfonate group works as a chelating ligand, thus stabilizing the rhodacycle intermediate, leading to the uncommon transformation.

Magnetic targeted nanoparticles double coated with β-cyclodextrin (β-CD) and chitosan (CS) were formed using a layer-by-layer model and their potential for hydrophobic drug delivery was evaluated in the study reported here. The resulting nanoparticles (NPs) had an average size of 102 nm and were spherical in shape. The double polymer layers ensured the colloidal stability and biocompatibility of the nanocarriers. Ibuprofen was chosen as the model drug. The nanocarriers possessed good magnetic properties and exhibited a high loading capacity that depended on the hybrid effects of electrostatic interaction and inclusion provided by the CS layer and the β-CD layer, respectively, which was confirmed using zeta potential analysis and a molecular modeling study. The in vitro release results revealed that the two-step release process consisted of an initial fast release and then a slower sustained release. Based on the Korsmeyer–Peppas model, the release mechanism was attributed to a mixed effect of swelling and a diffusion controlled release, which could be affected by pH, temperature and magnetic field. It is anticipated that the CS–CD–silica coated magnetic nanoparticles (SMNPs) will be a promising candidate as a nanocarrier for hydrophobic drugs.