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A novel drug nanocarrier with a magnetic core and a metal organic framework (MOF) shell was constructed by in situ growth of a three-dimensional network ZIF-8 on the surface of carboxy-functionalized Fe3O4. The resulting drug delivery system (DDS) showed strong superparamagnetism, boasting exceptional magnetization saturation at 11.15 emu g−1, an impressive magnetocaloric effect of a temperature rise of 12.9 °C within 6 min at 20 A, and a significant T2-weighted MR-image property. The drug encapsulation ability was investigated by loading a model drug namely curcumol (CUR) into the nanocarriers through supercritical solution impregnation (SSI) technology. The resulting Fe3O4@ZIF-8-CUR achieved a maximum loading content of 2.2 wt%, which was 3.4 times higher than that obtained using the ethanol impregnation process. As expected, a continuous drug release behavior of Fe3O4@ZIF-8-CUR was observed. This study presents a state-of-the-art methodology for designing biocompatible DDSs with magnetic responsiveness for advanced drug delivery applications. [ABSTRACT FROM AUTHOR]

We propose a facile and scalable in situ polymerization strategy to selectively introduce the active quinone-based components across the carbon nanotube (CNT) surface. It can be observed that the optimized poly(anthraquinonyl sulfide) (PAQS)/CNT composites exhibit excellent activity and selectivity with a H2O2 yield ratio of approximately 91% at 0.5 V (vs. RHE), together with satisfactory stability at 0.5 V over 20 h. The electrocatalytic performance is correlated with the synergistic effect between PAQS and CNTs. That is, PAQS grafted with abundant quinone groups facilitates the 2 e− ORR process to produce H2O2, and the conductive CNT scaffold is beneficial for the uniform distribution of PAQS and ensures the fast electron transport through the composites. [ABSTRACT FROM AUTHOR]

Reaction acceleration is a hot topic in recent years since it is very useful for rapid reaction screening and small-scale synthesis on a short timescale. It is known that the rates of chemical reactions are often accelerated in confined volumes (small droplets or thin films) where the unique chemical reactivities of molecules at the air–droplet/thin film interface, usually different from that in the bulk and gas phases, play a dominant role in acceleration. The Leidenfrost effect was employed to create small levitated droplets with no net charge. These droplets can accelerate many kinds of organic reactions. Our first accelerated synthesis of a series of organoimido-functionalized polyoxometalate (POM) clusters using Leidenfrost droplets with product analysis by electrospray ionization mass spectrometry (ESI-MS) demonstrated that this method can be successfully extended to the synthesis of inorganic/organic hybrids, a very promising area for developing POM-based functional materials. Comparable amounts of synthetic products [Mo6O18(NC6H4R)]2− (R = H (6), m/z 477; p-i-C3H7 (7), m/z 498; p-OCH3 (8), m/z 492; p-NO2 (9), m/z 500) were prepared within minutes in Leidenfrost droplets versus in hours in the corresponding bulk reactions under the same reaction conditions in the presence of the DCC catalyst, suggesting that both concentration and interfacial effects are pivotal in causing reaction acceleration in the Leidenfrost droplet. Compared to the conventional bulk reactions, the acceleration factors (AFs) were 92, 136, 126, and 89 for the four model reactions (1)–(4), respectively. We also found out that substitution affects the rate of reactions occurring in droplets, and hence the magnitude of AF. The rates increase in the order of R = NO2 < H < i-C3H7 < OCH3, in which the electron-donating groups (i.e., R = OCH3, i-C3H7) on the benzene ring are more favorable to the reaction than the electron-withdrawing group (i.e., R = NO2). This experimental result is in good agreement with the DFT calculation which indicates that the free-energy barriers for the direct imidoylization of POM with RNH2 are linearly correlated with the basicity constants (pKb) of amines. [ABSTRACT FROM AUTHOR]

Precise synthesis of well-controlled metal nanoparticles on various supports is one of the most challenging issues in their applications for the sustainable production of fuels and chemicals. We herein propose an effective method to generate small Ni nanoparticles at a high loading content of 20 wt% with homogeneous dispersion on Al2O3 regardless of low-temperature or high-temperature reduction. MIL-Al (110) was selected as the host for the fabrication of Ni nanoparticles with the size mainly at ∼5 nm after reduction at 600 or 800 °C. Conventional Al2O3 loaded Ni with the same amount shows a different behavior, that is, the particle size of Ni nanoparticles increases from 12.5 ± 1.8 nm after reduction at 600 °C to 20.0 ± 2.4 nm after reduction at 800 °C. The formation of a surface NiAl2O4 spinel structure on the Ni/Al2O3 sample and the inherent confinement effect from pristine MIL-110 (Al) contribute to the stabilization of small Ni nanoparticles with a high loading content under different reduction conditions. These results will open a possibility of rationally designing and fabricating highly dispersed metal nanoparticles on certain supports. [ABSTRACT FROM AUTHOR]

NO oxidation on transition metal-based perovskites has emerged as an effective strategy for reducing NOX in automotive and industrial exhaust. Magnetic Co3+ and nonmagnetic Ga3+ cations can change the magnetic properties of double perovskites, and also affect their oxidation activity with paramagnetic O2 and NO. Herein, La2GaMnO6 and La2CoMnO6 double perovskites with monoclinic structures were prepared via a facile molten-salt synthesis method. The coercive field (Hc), saturation magnetization (Bs), remanent magnetization (Br), and catalytic oxidation performance of La2CoMnO6 were obviously larger than those of the La2GaMnO6 double perovskites. Thus, it was concluded, the higher the magnetic properties, the better the catalytic oxidation performance over the double perovskites. [ABSTRACT FROM AUTHOR]

The effect of Co addition on the decolorization performance of the FePCCu amorphous alloy for degrading methylene blue (MB) is investigated. It is found that 100 mg L−1 MB solution can be rapidly degraded within 9 min via 0.5 g L−1 FeCoPCCu ribbon dosage and 1 mM H2O2 at 298 K at pH = 3. The amorphous state induced by the Co addition, nano-whisker and micro-crack structures formed during the decolorization process and local galvanic couples between bonds of metal–metalloid elements accelerate the electron and mass transfer of FeCoPCCu amorphous ribbons and result in their good catalytic ability. The catalytic performance of alloys with different Co additions is highly related to their corrosion resistance. Good environmental applicability and reusability of the alloys are also explored. The present work reveals that appropriate Co addition has a significant influence on the catalytic activity of Fe-based amorphous alloys, and this alloy is proposed as a new catalyst for sewage treatment. [ABSTRACT FROM AUTHOR]

In this work, we report the first bioluminescent probe BP-PS for detecting H2Sn with high specificity and sensitivity. Owing to the bioluminescence imaging without requiring an excitation light source, tissue autofluorescence is eliminated and BP-PS shows a high signal-to-noise ratio. Moreover, BP-PS was successfully utilized to visualize endogenous H2Sn in live cells and a murine model of bacterial infection. [ABSTRACT FROM AUTHOR]

LaMnO3 and LaCoO3 perovskite nanoparticles have sprung up as the platinum group-metal (PGM)-free catalysts of NO oxidation to reduce NOX in the exhaust. In this paper, we present mesoporous LaMnO3 and LaCoO3 with rhombohedral structures prepared by a facile molten-salt synthesis method. LaMnO3 and LaCoO3 achieved NO oxidation performance with the highest NO conversions of 85% and 94% at 300 °C, which may be improved by K and Na introduced via flux. [ABSTRACT FROM AUTHOR]

A bioluminescent probe, BP-HNO, which exhibits a turn-on response to nitroxyl with high sensitivity and selectivity, is reported for the first time in this work. BP-HNO is free from the interference of biological autofluorescence to afford a high signal-to-noise ratio for bioimaging, and was successfully applied to imaging nitroxyl in live cells and mice. [ABSTRACT FROM AUTHOR]

Homogeneous SnO2 hollow spheres have been synthesized through a hydrothermal method without a template, followed by in situ polymerization of PANI. The resulting SnO2 hollow spheres were uniformly deposited onto the surface or embedded into the PANI nanofibers to form a SnO2–PANI network structure. As electrode materials, the SnO2–PANI composites exhibit greatly enhanced specific capacitance (477 F g−1 at a current density of 1 A g−1) and superior cycling performance (no capacitance loss after 3000 galvanostatic charge–discharge cycles). These intriguing features are attributed to the interaction between the SnO2 hollow spheres and PANI network. On the one hand, the SnO2 spheres not only provide larger area for electrochemical reaction but also release volume expansion during the charge–discharge process. On the other hand, the conducting PANI improves electrical conductivity and maintains mechanical integrity of the composites as well. [ABSTRACT FROM AUTHOR]

In this study, ternary composites of reduced graphene oxide/molybdenum disulfide/polyaniline (rGEO/MoS2/PANI) were prepared via a two-stage facile synthesis including a hydrothermal reaction and polymerization at room temperature which makes the materials much easier for industrialization. The doping of reduced graphene oxide (rGEO) decreases the aggregation of MoS2 and enhances the electronic conductivities of MoS2, thus exhibiting better capacitance properties (531 F g−1 at 1 A g−1) and cycling stabilities (86.7% retained capacitance over 3000 cycles at 1 A g−1) of ternary composites than a uniform material (MoS2) or binary materials (MoS2/PANI). The combined effects between the three components make the composites obtain both pseudocapacitance and double-layer capacitance, which can be used to explain the improvement of electrochemical performances. [ABSTRACT FROM AUTHOR]

The CoFe Prussian blue analogue/carbon nanotube composite material was synthesized and applied to catalyze the reaction of epoxidation of styrene. Carbon nanotubes were used as catalyst carriers. The catalytic activity of this composite material was superior to the CoFe Prussian blue analogue and carbon nanotubes taken independently. The composite material indeed had a larger surface area and a better particle dispersion than the bulk Prussian blue analogue. Kinetic studies were also carried out. The reaction activation energy of the CoFe Prussian blue analogue alone was equal to 75.83 kJ mol−1, while the reaction activation energy of the composite material was equal to 35.67 kJ mol−1. A first order reaction with respect to the concentrations of catalyst, styrene and tert-butyl hydroperoxide was also determined. The composite catalyst could be reused for up to five cycles without any significant loss in conversion and selectivity. [ABSTRACT FROM AUTHOR]

Lysosomes are acidic organelles (approximately pH 4.5–5.5) and tracking the changes in lysosomal pH is of great biological importance. To address this issue, quite a few of fluorescent probes have been developed. However, few of these probes can realize the tracking of dynamic changes in lysosomal pH. Herein, we report a new lysosome-targeted ratiometric fluorescent probe (FR-Lys) by hybridizing morpholine with a xanthane derivative and an o-hydroxy benzoxazole group. In this probe, the morpholine group serves as a targeting unit for lysosome, the xanthane derivative exhibits a pH-modulated open/close reaction of the spirocycle, while the o-hydroxy benzoxazole moiety shows a pH modulated excited-state intramolecular proton transfer (ESIPT) process. Such a design affords the probe a ratiometric fluorescence response towards pH with pH values ranging from 4.0 to 6.3. The response of the probe to pH was fast and reversible with high selectivity. Moreover, this probe possesses further advantages such as easy synthesis, high photostability and low cytotoxicity. These features are favorable for tracking dynamic pH changes in biosystems. It was then applied for dynamic imaging pH changes in lysosomes with satisfactory results. [ABSTRACT FROM AUTHOR]

In this article, a new application of the room temperature ionic liquid, tetramethylammonium tetrafluoroborate, is described. This ionic liquid is used as a stabilizing agent and the reaction medium for the synthesis of CoFe Prussian blue analogue nanoparticles using N,N-dimethyl formamide as a complexing agent. The as-synthesized Prussian blue analogues were characterized by various techniques and were used to catalyze the reaction of epoxidation of styrene. The catalytic activity of Prussian blue analogues prepared in ionic liquid was superior to that of Prussian blue analogues prepared in aqueous solution. [ABSTRACT FROM AUTHOR]

The monoradical cation 1˙+ and anion 1˙− based on tetracene were generated by one-electron oxidation and one-electron reduction of the bulky tetracene (1), respectively, which contain the largest π-fused skeletons reported to date. For monoradical species, 1˙+ and 1˙−, EPR spectra and DFT calculation results indicate the spin density delocalized over the whole molecules. Notably, in the solid state, 1˙+ and 1˙−, respectively, pack into (1˙+)n and (1˙−-K-crown)n, characterized by single-crystal X-ray diffraction studies. The intermolecular interactions of 1˙+ and 1˙− are, respectively, through van der Waals forces and exchange couplings supported by metal ions. The monoradical cation polymer (1˙+)n was the first example based on PAHs. The EPR spectra at 90 K of 1˙+ and 1˙− all show forbidden transitions (Δms = ±2), indicating the existence of electronic coupling between the neighboring radicals, with respective 2J = −6.54 K and 2J = −0.22 K characterized by SQUID measurements. [ABSTRACT FROM AUTHOR]

Transition metal phosphides (TMPs) represent an important class of compounds with metalloid characteristics and good electrical conductivity, which are of great benefit to enhance electrochemical performances. Thus it is important to clarify the correlation between the electrochemical properties and the phosphating degree of the precursor. Herein, we report a superior electrode for battery-like capacitors based on NiCo2O4/NiCoP hetero-structure nanoflake-nanowire arrays grown on nickel foams using a one-pot facile hydrothermal approach and a controllable phosphorization treatment method. The Ni–Co precursor nanoflake-nanowire array based electrode treated with 500 mg NaH2PO2 shows significantly improved electrochemical performances with an ultrahigh specific capacitance of 2288.8 F g−1 and 1644 F g−1 at a current density of 1 A g−1 and 20 A g−1, respectively. The electrode also shows superior cycling stability. In addition, the NiCo2O4/NiCoP//AC device exhibits a relatively high energy density of 35.5 W h kg−1 at 750.4 W kg−1. The results suggest that this NiCo2O4/NiCoP nanoflake-nanowire array is a promising electrode material for high performance hybrid supercapacitor applications. [ABSTRACT FROM AUTHOR]

In this paper, large single crystals of diamond were synthesized in a pure Co–C system at 5.6 GPa and 1450–1470 °C. The diamond morphology, nitrogen content, and Co-related optical centres were investigated in depth. The results show that the diamonds are mostly bicrystalline or polycrystalline, with different surface defects, and the grown single crystals exhibit an octahedral morphology, with primarily {111} faces. The colour of the diamonds is brownish green-yellow and the nitrogen content is up to 980 ppm. The photoluminescence (PL) spectra show the presence of Co–V centres at 623 nm (V3Co2)0 and 843 nm (V1Co1+) in the diamonds. The intensity of Co-related optical centres at 623 nm and 843 nm gradually decreased with increases in the annealing temperature, and finally disappeared. Interestingly, Co–N complex defects appeared at 545 nm and 581 nm after annealing at 1700 °C, and the 524 nm Co–N complexes only appeared when the nitrogen almost completely aggregated after annealing up to 1800–1900 °C, and their intensity gradually increased with increasing annealing temperature. Furthermore, when nitrogen was removed from the growth system, the Co-related optical centres did not appear in the type IIa diamonds before and after annealing, which indicates that nitrogen impurities play an important role in the formation of Co-related optical centres. [ABSTRACT FROM AUTHOR]

Interfacial solar water evaporation is a sustainable and energy-saving water treatment technology to tackle the freshwater shortage issue. Low-cost, durable, and highly efficient photothermal materials play a crucial role in practical solar water evaporation. Here, banana is chosen as the raw material for solar water evaporation mainly due to its high yield and renewability. The carbonized banana foam (CBF) with interconnected porous structure ensures ultra-fast water supply and high solar absorption ability. The CBF-based system with a 3D structure possesses a high solar water evaporation rate of 1.51 kg m−2 h−1 and an energy conversion efficiency of 93.3% under 1 sun illumination. Notably, this banana-derived CBF presents robust mechanical strength that ensures long-term solar water evaporation, surpassing most fragile carbonized biomass materials. Furthermore, the CBF exhibits excellent water treatment performance, including seawater desalination and wastewater purification. This work provides new inspiration to develop simple, cost-effective, and green photothermal materials for applicable solar water treatment. [ABSTRACT FROM AUTHOR]

The development of high-performance electrode materials and the rational design of asymmetric structures are the two main keys to fabricating micro-supercapacitors (MSCs) with high energy density. Transition metal compounds, especially nickel–cobalt phosphides and hydroxides, are promising electrode materials with excellent pseudo-capacitance. However, they are rarely used in fabricating asymmetric MSCs (AMSCs) due to the limitations of the preparation method. In this work, we constructed hierarchical Ni–Co–P@LDH nanocomposites with outstanding mass specific capacitance (1980 F g−1 at 1 A g−1) via a multi-step electrodeposition method, which is employed with FeOOH to fabricate an interdigital AMSC device (Ni–Co–P@LDHs//PVA–KOH//FeOOH). The as-prepared device exhibits a high working voltage (1.4 V), a large specific capacitance (24.0 mF cm−2 at 0.14 mA cm−2), a high energy density (6.54 μW h cm−2 at a power density of 100 μW cm−2) and good cycling stability (86.5% of capacitance retention after 5000 cycles). This work may provide novel methods for the synthesis of high-performance nickel–cobalt composite materials and their potential applications in interdigital AMSC devices. [ABSTRACT FROM AUTHOR]

Studying the influence of oxygen on the growth and properties of diamond has research significance. In this paper, we created an oxygen-rich environment by adding Ni2O3 to the Fe–Ni–C system. Large single crystals of oxygen-containing diamond were successfully synthesized using the temperature gradient method (TGM) in a China-type large volume cubic high-pressure apparatus (CHPA) at 5.5–6.0 GPa and 1360–1600 °C. The results show that with the increase of the Ni2O3 content in the Fe–Ni–C system, the rate of diamond growth decreased while the conditions for diamond growth were enhanced. The morphology of the diamonds changed from {111}, {110} and {113} mixed faces to {111} dominant face. The IR results show that the presence of Ni2O3 increased the nitrogen content in diamonds from 237 ppm to 543 ppm. When 3.5 wt% Ni2O3 was added, A-centre nitrogen began to appear in the diamonds. The XPS results confirmed that oxygen successfully entered the diamond lattice in the form of C–O, C＝O, O–C＝O and N–O with a high concentration of Ni2O3 additives. Meanwhile, there were no obvious impurity inclusions and cracks in the diamond crystals. In addition, the Raman peak position of the diamond appeared to red shift, and the FWHM increased from 4.93 cm−1 to 5.52 cm−1. [ABSTRACT FROM AUTHOR]

Herein, we have managed to conceive and fabricate a core–shell structured triangle-like array, where a selenylation-treated MOF array was grown in situ on a conducting substrate as a highly conductive framework to support a high loading of Mo-doped nickel–cobalt LDH nanoflakes. This hierarchical electrode integrates the advantages of a defect-rich electronic state, large active area and rich reaction sites, delivering a high areal capacity of 5.16 C cm−2 and a high rate capability. [ABSTRACT FROM AUTHOR]

Developing efficient and durable catalysts for methanol oxidation is of great significance for direct methanol fuel cells. Herein, we realized the deposition of ultra-trace Pt nanoparticles by atomic layer deposition (ALD) onto a three-dimensional (3D) titanium nitride (TiN) nanowire array grown on carbon cloth (CC), in which the 3D TiN nanowires provide a stable platform for the Pt nanoparticles, besides the inherent properties of high corrosion resistance and conductivity. Owing to the superior characteristics of the 3D TiN nanostructure as the support material and the strong interaction between Pt and TiN, the Pt nanoparticles on the TiN nanowire array show an enhanced electrocatalytic activity toward methanol oxidation compared to a commercial Pt/C catalyst. This work provides an effective strategy to fabricate 3D high-performance electrocatalysts for future energy applications. [ABSTRACT FROM AUTHOR]