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Developing new low-cost and efficient proton-conducting materials remains an attractive and challenging task. Herein, sodium molybdate dihydrate is used as the source of molybdenum, mixed with transition metal chloride and 2-methylimidazole (2-MI), using the "one-pot method" to synthesize two crystalline proton conducting materials based on {P4Mo6} units: H14[C4H6N2]2[M(H2O)5] [M(H2O)2]2{M[(PO3)3(PO4)Mo6O15]2}·4H2O (M=Co and Fe) (1–2). Different from the common {P4Mo6}, we use H3PO3 to adjust the pH value, resulting in two different coordination modes of P atoms in the crystal structure. The structure is expanded into three-dimensional network by metal ions. At 75 °C and 98% relative humidity, the proton conductivity of compounds 1 and 2 are 1.33 × 10–2 S·cm−1 and 1.03 × 10–2 S·cm−1, respectively. The high proton conductivity is mainly attributed to the free state of 2-methylimidazole as the proton carrier, which has a fast migration rate. At the same time, 2-methylimidazole, coordination water, and {P4Mo6} anion form a hydrogen bond network to provide multiple pathways for the transmission of protons.

Fabricating proton exchange membranes (PEMs) with high ionic conductivity and ideal mechanical robustness through regulation of the membrane microstructures achieved by molecular-level hybridization remains essential but challenging for the further development of high-performance PEM fuel cells. In this work, by precisely hybridizing nano-scaled bismuth oxide clusters into Nafion, we have fabricated the high-performance hybrid membrane, Nafion-Bi12 -3 %, which showed a proton conductivity of 386 mS cm-1 at 80 °C in aqueous solution with low methanol permeability, and conserved the ideal mechanical and chemical stabilities as PEMs. Moreover, molecular dynamics (MD) simulation was employed to clarify the structural properties and the assembly mechanisms of the hybrid membrane on the molecular level. The maximum current density and power density of Nafion-Bi12 -3 % for direct methanol fuel cells reached to 432.7 mA cm-2 and 110.2 mW cm-2 , respectively. This work provides new insights into the design of versatile functional polymer electrolyte membranes through polyoxometalate hybridization.

Electrochemical N2 reduction to NH3 is an emerging energy technology, attracting much attention due to its features of mild reaction conditions and being non-polluting. In this work, we demonstrate that a well-defined cobalt tetraphenylporphyrin (CoTPP) molecule as a model catalyst exhibits good electrocatalytic nitrogen reduction activity in 0.1 M HCl electrolyte with an ammonia yield of 15.18 ± 0.78 μg h−1 mg−1cat. calculated by the indophenol blue method and a Faraday efficiency (FE) of 11.43 ± 0.74%. The catalyst also has satisfactory electrolytic stability and recycling test reusability. The activity displayed by the porphyrin molecular catalysts is attributed to the full exposure of the metal–N4 sites. To trace the source of ammonia, an isotope labeling experiment (15N2 as the feed gas) is used to calculate the ammonia yield via1H nuclear magnetic resonance (NMR), which is close to that of the indophenol blue method. In addition, we replace the central metal to prepare CuTPP and MnTPP, and they also show electrocatalytic nitrogen reduction reaction (NRR) ability. This work proves the feasibility and versatility of using metalloporphyrin molecules as model electrocatalysts for NRR and offers a new strategy for the further development of molecular NRR catalysts.

Exploring an efficient non-enzymetic electrochemical sensor towards the detection of H2O2 is of great significance for the practical health monitoring and environmental analysis. In this study, four Preyssler-type polyoxometalate-based organic–inorganic hybrid materials were synthesized as non-enzymatic H2O2 electrochemical sensors having the formulae (H2bimb)6H4[(Mn(H2O)3)2(μ-bimb)(Mn(H2O)4(Mn(H2O)5)0.75(Mn(H2O)4)0.25(Na(H2O)P5W30O110))2]·30.5H2O (1), (H2bimb)3H4[(Co(H2O)4)2(μ-bimb)(Na(H2O)P5W30O110)]·10H2O (2), {[(Cu(Hbimb)(H2O)(μ-bimb)Cu(Hbimb)(H2O))(Cu(H2O)2(μ-bimb)Cu(H2O)2)((Cu(H2O)2)0.5(μ-bimb)(Cu(H2O)3)0.5)H2(Na(H2O)P5W30O110)]·12H2O}n (3) and (H2bimb)2H[((Zn(Hbimb)(H2O)2)0.5)2(Zn(Hbimb)(H2O)4)2(Na(H2O)P5W30O110)]·8H2O (4) (bimb = 1,4-bis(1H-imidazol-1-yl)benzene). In the compounds 1–4, Preyssler {P5W30} clusters show abundant coordination modes, and support the transition metal–organic fragments to give fascinating diverse networks. When used as electrochemical sensors for H2O2 detection, compounds 1–4 exhibited good electrocatalytic activities with high sensitivity and low detection limit. Among them, compound 2 showed the lowest limit of detection of 0.13 mM with a high sensitivity of 4.35 μA mM−1 and fast response time of 1 s. Moreover, compound 2 displayed excellent electrochemical operational stability and anti-interference capacity. This study provides a good choice for the development of promising electrochemical non-enzymatic H2O2 sensors by employing Preyssler {P5W30}-based materials.

Noble metal nanoparticles (NMNPs) with excellent catalytic activity and stability play an important role in the field of environmental governance. A uniform distribution and a strong binding force with the carriers of the noble metal nanoparticles are important, but avoidance of the use of additional reducing agents is a promising direction of research. Herein, 2D ultrathin surfactant-encapsulating polyoxometalate (SEP) nanosheets constructed by the self-assembly of dodecyldimethylammonium bromide (DODA) and molybdophosphate (H3PMo12O40, PMo12) are designed to be versatile carriers for Ag nanoparticles. Under the synergistic effect of the well-arranged PMo12 units, encapsulating hydrophobic oleic acid (OA) and reductive molybdophosphate under Xe lamp irradiation, the silver oleate (AgOA)-derived Ag nanoparticles (5 ± 2 nm) are monodispersed on the DODA-PMo12 assemblies and form the Agx/DODA-PMo12 composite. The optimized Ag4.89/DODA-PMo12 composite exhibits high catalytic activity and stability in the degradation of 4-nitrophenol (4-NP), which reaches a superior rate constant of 6.49 × 10-3 s-1 and without significant deterioration after three recycles. This technique can be facilely promoted to other noble metal nanoparticles with excellent catalytic activity and stability.

Advanced hydrogen evolution reaction (HER) electrocatalysts matching with the chlor-alkali reaction serve as a vital link to realize the cost-effective and environmentally-benign co-production of hydrogen and chlor-alkali. The core problem in this field is to design and fabricate the HER electrocatalysts with high activity and stability under the harsh condition of chlor-alkali electrolysis. This review highlights the scientific, technical and engineering advances and challenges in this co-production of hydrogen and chlor-alkali. In detail, working mechanism and performance test criteria of HER electrocatalysts in chlor-alkali condition are provided. Recently developed HER electrocatalysts can be worked in chlor-alkali electrolysis are summarised, with a special emphasis on the relationship between their structure and electrolytic properties. Simultaneously, the latest progress in technology and engineering of co-production process is also listed. Finally, the opportunities and the direction of forward motion for this hydrogen and chlor-alkali co-production are also discussed.

Protein-based delivery systems can be used to increase the solubility and bioavailability of curcumin (Cur). In the current work, the synergistic effect of sodium caseinate (NaCas) and soluble soybean polysaccharide (SSPS) on improving the water solubility, stability and in vitro accessibility of Cur was investigated. Compared with SSPS, NaCas had a more prominent water solubilizing effect for Cur, at least ten times higher under the same conditions. This solubility increase was attributed to the formation of nanoscale colloidal complexes (~ 100 nm), exhibiting excellent dispersibility. The presence of SSPS did not significantly (p > 0.05) change the zeta potential (− 40 mV) or polydisperse index of the NaCas-based Cur nanocomplexes. However, SSPS significantly improved the environmental stability (pH, ionic strength and temperature) of the nanocomplexes, as well as the biological accessibility of Cur. Due to the good synergistic effect of SSPS and NaCas on the solubilization of Cur, the combination of NaCas/SSPS is expected to be an effective carrier for the preparation of water-soluble Cur nanocomplexes, and opens up the possibility of producing clarified Cur-enriched beverages.

It is vital to choose economical and environmentally friendly proton conductive materials to improve the performance of proton exchange membranes, which occupies a unique position in proton exchange membrane fuel cells. This paper reports a new proton conductive nanocomposite, that was named NbO2(OH)-PA prepared from phytic acid (PA) and NbCl5. NbO2(OH)-PA showed an excellent proton conductivity of 135 mS cm−1 at 85 °C and 97% relative humidity. In addition, NbO2(OH)-PA was combined with sulfonated poly (ether ketone) (SPEEK) in different proportions to form proton conductive membranes, that are labeled SPEEK-x NbO2(OH)-PA. SPEEK-0.9% NbO2(OH)-PA exhibited the best proton conductivity of 0.17 S cm−1 at 80 °C in water. This work may provide new ideas for improving proton conductivity of membranes through simple methods.

The electrocatalytic carbon dioxide (CO2) reduction reaction (CO2RR) involves a variety of electron transfer pathways, resulting in poor reaction selectivity, limiting its use to meet future energy requirements. Polyoxometalates (POMs) can both store and release multiple electrons in the electrochemical process, and this is expected to be an ideal “electron switch” to match with catalytically active species, realize electron transfer modulation and promote the activity and selectivity of the electrocatalytic CO2RR. Herein, we report a series of new POM-based manganese-carbonyl (MnL) composite CO2 reduction electrocatalysts, whereby SiW12–MnL exhibits the most remarkable activity and selectivity for CO2RR to CO, resulting in an increase in the faradaic efficiency (FE) from 65% (MnL) to a record-value of 95% in aqueous electrolyte. A series of control electrochemical experiments, photoluminescence spectroscopy (PL), transient photovoltage (TPV) experiments, and density functional theory (DFT) calculations revealed that POMs act as electronic regulators to control the electron transfer process from POM to MnL units during the electrochemical reaction, enhancing the selectivity of the CO2RR to CO and depressing the competitive hydrogen evolution reaction (HER). This work demonstrates the significance of electron transfer modulation in the CO2RR and suggests a new idea for the design of efficient electrocatalysts towards CO2RR., Polyoxometalates as electron regulators to promote the carbonyl manganese (MnL) electrocatalyst for highly efficient CO2 reduction in aqueous electrolyte.

The surface compositions and structure of oil bodies (OBs) are dependent on the oil crop, and these factors affect in vitro gastrointestinal digestion behaviors. Herein, a comparative study was conducted to examine the in vitro gastrointestinal digestion characteristics of two natural emulsions prepared with soybean seeds and rapeseed OBs during gastrointestinal digestion process. The average particle size of soybean OBs and rapeseed OBs emulsions was 0.46 and 5.02 µm, respectively. The droplet size of soybean seed and rapeseed OBs emulsions was large with relatively low zeta-potentials at 30 min digestion time in simulated gastric fluid condition. The droplet size of two natural OBs emulsions decreased with increasing digestion time in simulated gastric fluid condition. The average droplet size of both emulsions gradually decreased with increasing digestion time in simulated intestinal fluid conditions. The zeta-potential of the two emulsions increased with increasing digestion time in simulated intestinal fluid conditions. The extent of free fatty acids of soybean OBs emulsions was significantly higher than rapeseed after 20 min digestion time in simulated intestinal fluid conditions. The obtained results suggested that plant OBs could be useful as natural emulsifiers in the development of functional food and achieve controlled release of bioactive compounds from emulsions during gastrointestinal digestion.

Alloy phosphides as one of the most prospect materials are used in electrocatalytic hydrogen evolution reaction (HER) because of their adjustable composition, electronic structure and optimized activation energy for the electrocatalytic reactions. Herein, amorphous quaternary alloy phosphide NiCoFeP@NiCoP/NF with pagoda-like hierarchical nanoarrays structure grown on Ni foam is synthesized. The synergy effect between alloy components, the superior hierarchical nanoarrays structure and superaerophobic characteristic enables NiCoFeP@NiCoP/NF to be a pH-Universal electrocatalyst with high electrocatalytic performance toward HER and simulated seawater. To achieve 10 mA cm−2, this catalyst just required overpotential of 77, 136 and 184 mV in alkaline, acidic and neutral aqueous solution. The NiCo2O4@Ni [Fe (CN)6]/NF has stable HER performance (over 10 h) and a Faradic efficiency of 90.5% in simulated seawater. This work is expected to open up a new road for the construction of amorphous alloy phosphides with hierarchical nanoarrays structure for energy storage and conversion.

Developing new low-cost and efficient proton-conducting materials remains an attractive and challenging task. Herein, a Preyssler-type polyoxometalate derived coordination compound had been synthesized with a hydrothermal method, namely, H4.5NaCo5(2-MI)15.5(2-MI)3 [NaP5W30O110]·5H2O (1) (where 2-methylimidazole is abbreviated as 2-MI, and partial 2-MI was deprotonated). The structure was characterized by single crystal X-ray diffraction, PXRD, FT-IR, TG, CHN and ICP-OES elemental analyses. We studied the relationship between the crystal structure and proton conduction of compound 1 and found that the presence of 2-MI reduced the leakage of polyoxometalate under high relative humidity. Meanwhile, the strong interaction of the counter cation Na+ with water is beneficial to form more hydrogen bonds. Compound 1 showed the maximum proton conductivity with a value of 4.42 × 10−3 S cm−1 at 367 K and 97% RH. Kinetic investigation indicates that the proton conduction mechanism of compound 1 follows the vehicle mechanism.

Selective reduction of nitroarenes is extremely valuable in industrial chemical production. The main reduced products are usually aniline derivatives obtained using single-component noble- or transition-metal catalysts; however, other important products such as hydrazobenzene derivatives always involve in harsh conditions and multiple reaction steps. Here, we realize an unexpected switchable reduction of nitroarenes into aniline or hydrazobenzene derivatives with high yield and selectivity just by controlling the molar ratio of nitroarenes to N2H4·H2O with a nickel–tungsten carbide composite nanocatalyst loaded on carbon (Ni-WC/C). A series of control experiments and density functional theory (DFT) calculations indicate that the multiple interfaces between Ni and WC can induce a synergistic effect, significantly modulating the electronic structure of the Ni-WC/C catalyst, and endowing the catalyst with switchable selectivity and high activity for the reduction of nitroarenes by hydrogenation. This synergistic multi-interfacial catalyst may offer a new way to design and explore highly efficient and selective catalysts for the controllable reduction of nitroarenes and similar hydrogenation reactions.

Development of new direct methanol fuel cell catalyst is a hot topic of current research. In this article, we adopted a simple method of synthesizing a PtNi alloy catalyst in one step at room temperature. In order to study the optimum proportion of platinum salt and nickel salt in the experiment by changing the molar ratio of platinum and nickel in the solution, five different proportions of PtNi alloy catalysts were obtained. The successful synthesis of PtNi alloy catalyst was proved by XRD and other characterization methods. The electrochemical properties of the above electrocatalysts were investigated using CV, LSV and other testing methods. The results show that PtNi-4 alloy catalyst exhibits excellent catalytic activity in both methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) tests, and their initial potential and current density are similar to commercial Pt/C catalysts in ORR. In summary, the prepared PtNi-4 alloy catalyst can be used as an anode or cathode catalyst in direct methanol fuel cells.

Triptolide is a major active ingredient isolated from the traditional Chinese herb Tripterygium wilfordii Hook F. However, its use in clinical practice is limited due to its severe hepatotoxicity. Autophagy, a highly conserved intracellular process, is essential for maintaining cytoplasmic homeostasis. Considering that abnormalities in autophagy are closely associated with drug-mediated hepatotoxicity, we applied human normal liver HL7702 cells to elucidate the roles of autophagy in triptolide-induced hepatotoxicity. Our study revealed that triptolide was cytotoxic to HL7702 cells. It markedly increased autophagosome formation and expression of autophagy-related proteins, namely Beclin1 and microtubule-associated protein 1 light chain 3II, and induced oxidative stress. These proautophagic effects were counteracted by pretreatment with N-acetylcysteine, a reactive oxygen species scavenger. Moreover, the pharmacological suppression of autophagy further exacerbated triptolide-elicited decrease in cell viability, increase in lactate dehydrogenase leakage, and activation of apoptosis proteases (caspase 3 and caspase 9). Our findings suggest that triptolide-induced oxidative stress consequently enhances autophagic activity, and autophagy is a cytoprotective mechanism against triptolide-induced cytotoxicity in HL7702 cells.

A novel compound containing active amine groups of polyphosphazene (PBFA) was successfully synthesized and applied as a reactive flame-retardant additive in epoxy (EP) resin. It was synthesized from N-aminoethylpiperazine and hexachlorocyclotriphosphazene using a simple method, and its structure was well-characterized. The results indicated that introducing PBFA into EP composites significantly improves the resistance to fire and suppresses smoke generation. An EP composite with 9.0 wt% PBFA can pass the vertical burning tests V-0 rating, the peak heat release rate and total heat release of the sample decreased by 46.7% and 29.3%, respectively. Moreover, it decreased the total smoke release by 48.0%. Thermogravimetric analysis showed that the presence of PBFA can accelerate EP decomposition at comparatively low temperatures and lead to the formation of a stable char layer, which protects the matrix from fire, therefore improving the amount of char residue at 800 °C. The degree of small molecule degradation characterized by gas chromatograph/mass spectrometer, which was lower than that of pure EP, demonstrating that PBFA reduces the risk of fire. The glass transition temperature of EP composites increased with the amount of PBFA increasing owing to the presence of active amine groups. Notably, its mechanical properties were not degraded.

Background During the last decade buckwheat was reported to have positive health effects. The present study investigated a high-polyphenol buckwheat protein (Fagopyrum esculentum Moench) prepared by enzyme-assisted processing, together with its physicochemical properties, in vitro digestibility, and antioxidant activity. Results Buckwheat protein prepared from the synergistic enzymatic action of α-amylase and amyloglucosidase (E-BWP) had much higher polyphenol content than buckwheat protein prepared by isoelectric precipitation (I-BWP) or salt extraction (S-BWP). Rutin degraded during the process, giving quercetin. The protein constituents and amino acid composition of E-BWP were very similar to those of native buckwheat and were able to meet the WHO/FAO requirements for both children and adults. During in vitro digestion, E-BWP showed anti-digestive behavior with a nitrogen release that was lower than that of I-BWP or S-BWP. The positive effect of the polyphenol content of E-BWP resulted in a higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) content and greater reducing activity. Conclusion Buckwheat protein with high polyphenol content was successfully developed by enzyme-assisted processing. It had a well-balanced amino acid profile, antidigestive behavior, and high antioxidant activities. The results suggest that enzyme-assisted processing is promising in the production of polyphenol-enriched cereal protein, contributing higher functionality with good nutritional and antioxidant properties. © 2018 Society of Chemical Industry.

Aromatic amino compounds are important and universally used chemical intermediates in a wide range of industrial fields. Thus, their production with high efficiency and selectivity under ambient conditions is expected and demanded in modern industry. Herein, a series of superfine CoNi alloy nanoparticles embedded in Al2O3 nanosheet (CoxNi1-x/Al2O3, where x represents the content of Co in the precursor) catalysts was fabricated from CoNiAl-LDH and used to catalyze the tandem dehydrogenation of ammonia borane (AB) and hydrogenation of nitroaromatics to the corresponding amines. Systematic experiments indicate that the composition, size, morphology and catalytic performance of the CoxNi1-x/Al2O3 catalysts can be easily controlled by changing the content of Ni in the CoNiAl-LDH precursor. Particularly, Co0.67Ni0.33/Al2O3 exhibited the best tandem catalytic performance among the six samples. This as-prepared catalyst not only showed a moderate turn-over-frequency value (TOF: 34.5 molH2 molCo0.67Ni0.33-1 min-1 at 298 K without base or additives) and relatively low activation energy (32.4 kJ mol-1) for the dehydrogenation of AB, but also superior catalytic activity (conversion yield reaching up to 100%) and selectivity (>99%) for the tandem reductive transformation of in excess of sixteen types of nitroaromatics to aromatic amines. Density functional theory (DFT) calculations suggest that the construction of the CoNi alloy optimized the electronic structure with respect to the pure component, promoting its activity for AB hydrolysis and nitroaromatics hydrogenation. Finally, the catalyst could be easily recycled using a magnet due to the magnetic properties of the Co0.67Ni0.33 alloy.

A new super proton-conducting {H6Bi12O16}/GO membrane with high chemical and thermal stability was synthesised via a vacuum-assisted filtration method., Proton exchange membrane fuel cells are still limited as state-of-art proton exchange membranes perform poorly at high and low temperature and are easily damaged by harsh electrochemical conditions such as reactive peroxide species. One effective solution to this issue is to develop new types of proton conductive materials that are capable of working in a broad temperature range. A simple vacuum-assisted filtration method is employed to obtain a well-ordered new proton-conducting membrane by immobilizing nanosized bismuth oxide clusters [H6Bi12O16] (NO3)10·6(H2O) {H6Bi12O16} onto graphene oxide (GO) supports (named as {H6Bi12O16}/GO). {H6Bi12O16}/GO is stable in acidic media and has high proton conductivity over the temperature range from –40 to 80 °C. The proton conductivity of the {H6Bi12O16}/GO membrane is 0.564 S cm–1 at 80 °C in aqueous solution (in plane), and 0.1 S cm–1 at 80 °C and 97% RH (out of plane), respectively. Without loss of high proton conductivity, the membrane also exhibited 100-fold lower methanol permeability than a Nafion 117 membrane. Moreover, {H6Bi12O16}/GO displayed good catalytic decomposition of hydrogen peroxide and superior humidity response and recovery properties. These advantages mean that {H6Bi12O16}/GO holds great promise as a solid-state electrolyte that can potentially be applied in energy conversion devices in the future.

To investigate the effect of maternal zinc deficiency on learning and memory in offspring and the changes in DNA methylation patterns.Pregnant rats were divided into zinc adequate (ZA), zinc deficient (ZD), and paired fed (PF) groups. Serum zinc contents and AKP activity in mother rats and offspring at P21 (end of lactation) and P60 (weaned, adult) were detected. Cognitive ability of offspring at P21 and P60 were determined by Morris water maze. The expression of proteins including DNMT3a, DNMT1, GADD45β, MeCP2 and BDNF in the offspring hippocampus were detected by Western-blot. The methylation status of BDNF promoter region in hippocampus of offspring rats was detected by MS-qPCR.Compared with the ZA and PF groups, pups in the ZD group had lower zinc levels and AKP activity in the serum, spent more time finding the platform and spent less time going through the platform area. Protein expression of DNMT1 and GADD45b were downregulated in the ZD group during P0 and P21 but not P60 compared with the ZA and PF group, these results were consistent with a reduction in BDNF protein at P0 (neonate), P21. However, when pups of rats in the ZD group were supplemented with zinc ion from P21 to P60, MeCP2 and GADD45b expression were significantly downregulated compared with the ZA and PF group.Post-weaning zinc supplementation may improve cognitive impairment induced by early life zinc deficiency, whereas it may not completely reverse the abnormal expression of particular genes that are involved in DNA methylation, binding to methylated DNA and neurogenesis.

Tussilagone is a sesquiterpenoid extracted from Tussilago farfara and is used as an oriental medicine for asthma and bronchitis. Although previous studies have shown that tussilagone has an inhibitory effect on platelet aggregation, no studies have been performed to investigate its precise effect on platelets, and the underlying mechanism remains unclear. In the present study, we showed that tussilagone inhibited platelet aggregation induced by collagen, thrombin and ADP, as well as platelet release induced by collagen and thrombin, in mice. Tussilagone decreased P-selectin expression and αIIbβ3 activation (JON/A binding) in activated platelets, which indicated that tussilagone inhibited platelet activation. Moreover, tussilagone suppressed platelet spreading on fibrinogen and clot retraction. The levels of phosphorylated Syk, PLCγ2, Akt, GSK3β, and MAPK (ERK1/2 and P38) and molecules associated with GPVI downstream signaling were downregulated in the presence of tussilagone. In addition, tussilagone prolonged the occlusion time in a mouse model of FeCl3-induced carotid artery thrombosis and had no effect on mouse tail bleeding time. These results indicate that tussilagone inhibits platelet function in vitro and in vivo and that the underlying mechanism involves the Syk/PLCγ2-PKC/MAPK and PI3K-Akt-GSK3β signaling pathways downstream of GPVI. This research suggests that tussilagone is a potential candidate antiplatelet drug for the prevention of thrombosis.

A coordination polymer with ordered and non-acidic water-cluster guest molecules, [Zn(cis-chdc)(bpp)]·6H2O (denoted as Zn2-(H2O)12, H2chdc = 1,4-cyclohexanedicarboxylic acid; bpp = 1,3-bis(4-pyridyl)propane), which captures a kind of (H2O)12 cluster inside the cavity, is found to be an efficient proton conducting solid electrolyte. Zn2-(H2O)12 has a high conductivity of 0.241 mS·cm−1 at 318 K and 95% RH (relative humidity), which is higher than the other kinds of water-only guested coordination polymers (CPs). The configuration of the water clusters has been described and the role it plays in the process of proton transportation has been investigated preliminarily.

The rational design and development of efficient and affordable enzyme-free electrocatalysts for electrochemical detection are of great significance for the large-scale applications of sensor materials, and have aroused increasing research interest. Herein, we report that a typical polyoxometalate (POM)-based metal-organic framework (NENU5) that was hybridized with ketjenblack (KB) was a highly efficient electrochemical catalyst that could be used for the highly sensitive nonenzymatic detection of H2 O2 . The composite catalyst exhibited superb electrochemical detection performance towards H2 O2 , including a broad linear range from 10-50 mm, a low detection limit of 1.03 μm, and a high sensitivity of 33.77 μA mm-1 , as well as excellent selectivity and stability. These excellent electrocatalytic properties should be attributed to the unique redox activity of the POM, the high specific surface area of the metal-organic framework (MOF), the strong conductivity of KB, and the synergistic effects of the multiple components in the composites during the electrolysis of H2 O2 . This work provides a new pathway for the exploration of nonenzymatic electrochemical sensors.

Two kinds of activated carbon spheres (ACS)-supported metal oxides, ACS-supported Fe3O4 (ACS@Fe3O4) and ACS-supported NiO (ACS@NiO), were synthesized and used as flame retardants for reducing smoke release volume and fire hazard in flexible poly(vinyl chloride) (PVC). Scanning electron microscope measurement, Fourier transform infrared spectrum, X-ray diffraction and thermogravimetric analysis (TGA) were utilized to investigate the morphology, chemical structure and stability of the flame retardants. The TGA coupled with mass spectrometry (TG-MS) results of PVC composites showed that ACS could retard the heat and oxygen transfer between gas and polymers. Under the same condition, ACS@Fe3O4 could promote the dehydrochlorination reaction of PVC in lower temperature, while the ACS@NiO could make the dehydrochlorination reaction faster. Therefore, both ACS@Fe3O4 and ACS@NiO effectively promoted the cross-linked carbonization reaction of PVC and then generated a large amount of stable char residues. Limiting oxygen index (LOI) and cone calorimeter test results of the PVC composites showed that ACS@Fe3O4 and ACS@NiO were much more efficient than ACS alone to improve the flame retardancy and smoke suppression of PVC. The incorporation of ACS@Fe3O4 and ACS@NiO increased the LOI from 24.9 to 27.4% and 26.9% and reduced the peak of heat release rate by 47.2 and 30.8%, respectively, compared with pure PVC.

Polyoxometalates (POMs) show considerable catalytic performance toward the selective oxidation of alkenes to aldehydes, which is commercially valuable for the production of pharmaceuticals, dyes, perfumes, and fine chemicals. However, the low specific surface area of POMs as heterogeneous catalysts and poor recyclability as homogeneous catalysts have hindered their wide application. Dispersing POMs into metal-organic frameworks (MOFs) for the construction of POM-based MOFs (POMOFs) suggests a promising strategy to realize the homogeneity of heterogeneous catalysis. Herein, we report two new POMOFs with chemical formulas of [Co(BBTZ)2][H3BW12O40]·10H2O (1) and [Co3(H2O)6(BBTZ)4][BW12O40]·NO3·4H2O (2) (BBTZ = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene) for the selective oxidation of alkenes to aldehydes. Compound 1 possesses a non-interpenetrated three-dimensional (3D) cds-type open framework with a 3D channel system. Compound 2 displays a 3D polyrotaxane framework with one-dimensional channels along the [100] direction. In the selective oxidation of styrene into benzaldehyde, compound 1 can achieve a 100% conversion in 4 h with 96% selectivity toward benzaldehyde, which is superior to that of compound 2. A series of control experiments reveal that the co-role of [BW12O40]5- and Co2+ active center as well as a more open framework feature co-promote the catalytic property of the POMOFs in this case. This work may suggest a new option for the development of POMOF catalysts in the selective oxidation of alkenes.

The hydrogen evolution reaction (HER) produces clean hydrogen through an electrochemical process. However, new nonprecious-metal electrocatalysts for the HER are required to reduce the consumption of energy. Herein, we report a new Co2 P/WC nano-heterojunction that consists of Co2 P and WC composite phases coated with a few-layer N-doped graphitic carbon shells (Co2 P/WC@NC). The composite was prepared by a one-step annealing of the polyoxometalate Na9 (NH4 )5 [{(B-α-PW9 O34 )Co3 (OH)(H2 O)2 (Ale)}2 Co]⋅35 H2 O (Co7 P6 W18 ) and dicyandiamide (DCA). The preparation method consisted of the simultaneous phosphorization of Co and carbonization of W in a confined space to isolate a Co2 P/WC nano-heterojunction phase for the first time. Co2 P/WC@NC facilitated the generation of hydrogen in the electrolysis process, which had an overpotential of only 91 mV at a current density of 10 mA cm-2 in the acid solution; an excellent HER performance (2 H+ +2 e- →H2 ) and Tafel slope (40 mV dec-1 ) as well as durability over a period of 50 h were achieved. Theoretical calculations showed that the Co2 P, WC, and Npyridinic C dopants in the material synergistically promoted the HER activity rather than the individual constituents. Furthermore, Co2 P/WC@NC nano-heterojunctions showed good HER performance in the whole pH range of electrolytes and considerable durability in acidic media containing transition metal ions, which may attract more attention for the exploration and optimization of nano-heterojunction catalysts for the HER.

A series of flame-retardant ethylene–vinyl acetate (EVA) composites with different contents of aluminum phosphate (AHP) and Trimer were prepared. The synergistic flame-retardant effects of the Trimer with AHP in EVA/AHP blends were studied by limiting oxygen index (LOI) tests, UL-94 tests, cone calorimeter tests, thermogravimetric analysis, and scanning electron microscopy (SEM). The LOI and UL-94 results showed that the system containing AHP and Trimer was very effective in improving the flame retardancy of EVA. When the mass ratio of AHP and Trimer was 3:1, the highest flame retardancy could be obtained, and when the flame-retardant loading was 30 wt%, the EVA/AHP/Trimer (7.5%) sample could achieve the V-0 rating in UL-94 tests, at the same time, its LOI value was 24.4%. The TG and DTG results showed that the addition of flame retardants catalyzes EVA decomposition in the first stage and generates a more stable char residue in the second stage. Consequently, an efficient reduction in the flammability parameters, such as heat release rate, total heat release, smoke production rate, and total smoke production could be observed. In addition, it was observed from the SEM observations of the morphological features that the AHP and Trimer combination, at the optimum proportion, could promote the formation of compact charred layers and prevent their cracking, which effectively protected the underlying materials from burning.

Exploring high-performance electrocatalysts for sustainable hydrogen production is an essential prerequisite of a further hydrogen economy. Integrating multiple interfaces in two-component electrocatalysts is expected to be a feasible strategy to optimize the intrinsic electronic structure of hybrid catalysts and improve their catalytic property. Herein, we report a new type of multi-interfacial nickel/tungsten carbide (Ni/WC) hybrid nanoparticles anchored on N-doped carbon sheets (Ni/WC@NC), which can efficiently and robustly catalyze the hydrogen evolution reaction (HER) with striking kinetic metrics in a wide pH range. In 0.5 M H2SO4, Ni/WC@NC displays a low overpotential (53 mV at current density of 10 mA cm−2), a small Tafel slope (43.5 mV dec−1), a high exchange current density (0.83 mA cm−2), as well as excellent stability, outperforming most of the current noble-metal-free electrocatalysts. A series of controlled experiments, DFT calculations and in situ XAS measurements reveal that the remarkable HER activity is mainly attributed to abundant interfaces between Ni and WC domains, which induce a synergistic optimization of the electronic configuration of Ni and WC through electron transfer process from WC to Ni along with potential mass transport, thus promoting the HER kinetics and accelerating the reaction. Our work suggests a potentially powerful interface-engineering strategy for designing high-performance electrocatalysts for the HER.

Molybdenum carbides are considered as one type of privileged noble-metal-free electrocatalysts for hydrogen evolution reactions (HER) due to their d-band electron structure, which is similar to Pt. Especially, the electronic structure of such materials can be further adjusted by elemental doping to improve their electrocatalytic activity. Herein, we selected the Anderson-type polyoxometalates (POMs) (NH4)n[TMMo6O24H6]·5H2O (TM = Ni2+, Co2+, n = 4; TM = Fe3+, Cr3+, n = 3) as precursors to prepare new transition-metal-doped Mo2C materials. When these POMs were mixed with dicyandiamide (DCA) by solid grinding, and carbonized at a high temperature, a series of Ni-, Co-, Fe-, and Cr-doped Mo2C composite nanoparticles covered by few-layer graphitic carbon shells (abbr. TM-Mo2C@C) were obtained. All these nanoparticles possess a similar size, morphology, and TM/Mo component ratio, and thus it is feasible to systematically investigate the influence of different TM dopants on the electrocatalytic activity of Mo2C for HER. Both electrocatalytic experiments and DFT calculations reveal that TM dopants have a significant effect on the hydrogen binding energy (ΔGH*) and the catalytic activity of Mo2C. The sequence of HER electrocatalytic activity is as follows: Ni-Mo2C > Co-Mo2C > Fe-Mo2C > Cr-Mo2C. As a result, Ni-Mo2C@C possesses the best HER performance, which required an overpotential of 72 mV at a current density of 10 mA cm-2 and the Tafel slope is 65.8 mV dec-1. This work suggests a shortcut to reasonably investigate the effects of elemental doping on molybdenum carbides and explore new high-efficient and low-cost electrocatalysts for HER.

Developing highly active, durable and economical noble-metal-free electrocatalysts for the hydrogen evolution reaction (HER) plays a crucial role in the future hydrogen economy. Herein, ultrafine cable-like WC/W2C heterojunction nanowires (NWs) covered by few-layer N-doped graphite-like carbon (labeled WC/W2C@C NWs) have been firstly accomplished via a simple two-step pyrolysis treatment of W18O49 NWs precursor, exhibiting tunable phase composition, excellent HER activity, fast kinetic metrics and remarkable stability along the entire pH range. With the optimized phase composition, WC/W2C@C NWs (WC : W2C ≈ 1 : 1.3) display the low overpotentials of 69 mV and 56 mV at the cathodic current density of 10 mA cm−2 and small Tafel slopes of 52 and 59 mV dec−1 in 0.5 M H2SO4 and 1 M KOH, respectively. DFT calculations and experimental results demonstrate that such prominent performance towards the HER was mainly attributed to abundant interfaces between WC and W2C phases in the cable-like heterojunction nanowires which may exert both the high HER activity of W2C and the excellent electrochemical stability and conductivity of WC. Furthermore, the one-dimensional (1D) nanowire morphology and graphite-like carbon shells also promote the conductivity of the whole electrocatalytic material. This work presents a new route to accomplish the morphology control, composition and electronic regulation so as to boost the HER performance of tungsten-carbide-based electrocatalysts, providing new guidance for exploring efficient noble-metal-free electrocatalysts.

Methanol oxidation is a very important reaction in diret methanol fuel cells. Developing stable and efficient Pt-based catalysts with a convenient method has been on the stage recently. Herein, we employed a convenient one-pot method to synthesize Pt nanoparticles encapsulated by polyoxometalates (POMs) spreading on a few layers of graphene oxide with a nickel foam as a conductive substrate. Four kinds of samples with different Pt loadings were finally obtained by adjusting the H2PtCl6 concentration, named as PPGN-n (n = 1, 2, 3, 4). The microscopic structure of the sample was characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. It was proved that small-sized Pt nanoparticles with a diameter of ca. 2.47 nm spreaded on graphene oxide (GO) with the nickle foam support were successfully synthesized. The synthesized electrocatalysts exhibited higher electrocatalytic activities than commercial Pt/C for methanol oxidation in electrocatalytic tests. The mass activity of PPGN-1 of 250.6 mA mg−1 can be achieved. During the synthesis, POM was used as a bifunctional reagent; as a reductant for reducing chloroplatinic acid and a stabilizer for the regulation of the Pt nanoparticle size simultaneously. POM cooperated rapid synthesis of Pt nanoparticles can offer a new route for designing and synthesising electrocatalysts.

Although significant efforts have been devoted to designing efficient electrocatalysts for the oxygen evolution reaction, further progress is still needed regarding modulating the microstructures of electrocatalysts to further improve catalytic activity. Herein, utilizing ionic compound NaF and heteroatom-N-rich urea as morphology directing reagents, ultralong needle-like N-doped Co(OH)F supported on carbon fiber paper has been synthesized through a one-step hydrothermal method. Specifically, the hydrothermal kettle provides a stable environment for the formation of ultra-long needle-like structures. Meanwhile, with the addition of halogen anion F− and heteroatom N, a wealth of oxygen vacancies are obtained, and the OER activity is enhanced. The as-prepared N-doped Co(OH)F-CFP (N:Co(OH)F-CFP) has excellent hydrophilicity, which facilitates its contact with the electrolyte and then accelerates the passing of electrons back and forth between the surface of the material and the electrolyte. Under alkaline conditions, N:Co(OH)F-CFP's OER activity is superior to that of IrO2. Its potential can reach 1.540 V (vs. RHE) at 10 mA cm−2 with a Tafel slope of 69.75 mV dec−1 in 1 M KOH solution.

Transition metal (TM) oxides and hydroxides are one of the important candidates for the development of durable and low-cost electrocatalysts towards water splitting. The key issue is exploring effective methods to improve their electrocatalytic activity. Herein, we report a new type of P-doped Ni(OH)2/NiMoO4 hierarchical nanosheet array (abbr. P-Ni(OH)2/NiMoO4) grown on Ni foam (NF), which can act as a highly efficient electrocatalyst towards overall water splitting. Such a composite was obtained by a three-step preparation process. In the first two hydrothermal reactions, the crystalline Ni(OH)2 hierarchical nanosheet arrays were grown on NF and then the low crystallinity NiMoO4 was grafted on the Ni(OH)2 nanosheets. In the third phosphorization step, P element was doped into the composite Ni(OH)2/NiMoO4. Electrocatalytic experiments show that P-Ni(OH)2/NiMoO4 possesses a smaller overpotential (60 mV) and lower Tafel slope (130 mV dec−1) toward HER in 1 M KOH. When it was employed as an integrated water splitting catalyst, only a potential of 1.55 V was required to achieve a current density of 10 mA cm−2. This catalytic activity is even better than those of electrolyzers constructed with noble metals Pt/C∥IrO2. The superior electrocatalytic performance of P-Ni(OH)2/NiMoO4 can be attributed to the high quality of crystalline Ni(OH)2 nanosheet arrays grown on NF, which dramatically improve the conductivity. Furthermore, the hierarchical structure not only increases the surface area and exposes more catalytically active sites, but also provides a superaerophobic surface, which helps to accelerate the release of generated bubbles. Moreover, the synergistic effects between P-Ni(OH)2 and P-NiMoO4 efficiently promote the HER and OER processes also. This work may suggest new a way to explore TM oxide/hydroxide-based durable electrocatalysts with highly efficient electrocatalytic activities towards overall water splitting.

The development of highly active and stable electrocatalysts for HER has been received extensive attention. Among these, minimizing the Pt usage and promoting its utilization efficiency are essential prerequisites for a future hydrogen economy. Herein, we use a new e-Keggin-type polyoxometalate-based metal–organic framework H3[Zn4(bimb)2][PMoV8MoVI4O40]·12H2O (POMOF-1) as a support to load a low amount of ultrasmall Pt nanoparticles (NPs), and then mix this material with Ketjenblack carbon (KB) to form a new composite catalyst (Pt@POMOF-1/KB). This composite catalyst shows a low Pt loading amount of 0.43 wt% and the average size of the Pt NPs is 1.5 nm. Pt@POMOF-1/KB exhibits a remarkable HER performance in 0.5 M H2SO4. It only requires an overpotential to of 23 mV to observe a current density of 10 mA cm−2, which is superior to that of 20% Pt/C. The mass activity of Pt@POMOF-1/KB is almost 100 and 37 times that of 20% Pt/C at overpotentials of 50 and 100 mV, respectively, as a consequence of the very low noble-metal loading. This result may provide an approach to meet the cost requirements for large-scale applications.

Covalent organic frameworks (COFs), as new promising photocatalysts, have aroused great interests, but the systematic study on the structure–property relationship of COF-photocatalysts is scarcely reported. Herein, six β-keto-enamine-based COFs with different backbones and substituents have been prepared. Through systematic experiments and DFT calculation, the structure–property relationships of the composition, structure and substituents of COFs on their spectra, specific surface area, hydrophobicity, electronic structures, carrier separation and photocatalytic hydrogen production have been studied. We explore that the backbone of COFs has important influence on their band gap, spectral absorption and carrier separation. While the substituents affect the band positions, surface area and hydrophobicity of COFs. Comprehensively, TpPa-Cl2 (constructed by 1,3,5-triformylphloroglucinol and 2,5-dichloro-1,4-phenylenediamine) exhibits the best area-normalised photocatalytic performance for hydrogen production, which is about 11.73 µmol·m−2·h−1 (0.01 g catalysts) with apparent quantum efficiency of 17% at 400 nm. This work provides a new perspective for the rational design and construction of efficient COF-photocatalysts.

The aims of this study were to investigate the effect of xanthophylls (Xan) on the colloidal property and interfacial activity of zein hydrolysate (ZH), and the influence of Xan on the colloidal delivery capacity of ZH was also studied by the construction of emulsions and colloidal particles systems. The result indicated that compared with color-free ZH (CF-ZH), ZH was more sensitive to pH and showed obvious aggregation behavior at acidic pH. ZH exhibited lower critical micelle concentration compared with CF-ZH, suggesting the higher amphiphilic characteristic of ZH. The results from interfacial activity investigations showed that ZH exhibited higher interfacial activity compared with CF-ZH, and the thickness and intensity of the interfacial layer constituted by ZH was increased as a result of the existences of Xan. Compared with CF-ZH, the emulsions stabilized by ZH possessing smaller size and higher physical stability, and the curcumin nanoparticles fabricated in ZH solutions showed higher encapsulation efficiency, smaller particle size, better monodispersity and higher zeta potential. In conclusion, the presence of Xan in ZH obviously changed the colloidal property and improved interfacial activity and colloidal delivery capacity of ZH itself, and it endowed ZH with more extensive application prospects.

A series of polyoxometalate silver salts (Ag n POM) with low solubility were prepared by mechanically grinding the dry solid mixture of Keggin-type polyoxotungstates with different central heteroatoms and the silver nitrate. The as-prepared Ag n POM solids were further UV-irradiated, resulting in the generation of metallic silver nanoparticles (NPs) on the surface of the Ag n POM salts. Thus, a series of composite Ag n POM materials loaded with different amount of Ag NPs (Ag0 x /AgI n POM) were obtained. The UV-Vis diffuse reflectance spectra show that the intensities of absorbing bands of the composite materials in visible area have been enhanced due to the plasmon resonance of Ag NPs. Such composite materials exhibit enhanced visible light-driven photocatalytic performances for dye degradation and the reduction of Cr(VI). Furthermore, the loading amount of Ag NPs on the photocatalysts can be tuned by changing the negative charge of POM anions. As a result, the relevant photocatalytic activity of such composite materials can be also adjusted.

During the exploration of highly efficient noble-metal-free electrocatalysts for the hydrogen evolution reaction (HER), a promising and challenging strategy is to fabricate composite nanocatalysts by finely tuning metal and/or nonmetal element components. Herein, we report a new HER electrocatalyst, which is composed of molybdenum phosphide and molybdenum carbide composite nanoparticles (NPs) coated by few-layer N-doped graphitic carbon shells (denoted as MoP/Mo2C@C). Such a new combination mode of electrocatalysts is realized by a one-step annealing route with the mixture of a Mo/P-based polyoxometalate (POM) and dicyandiamide. On the basis of this method, the simultaneous phosphorization and carbonization in a nanoscale confined space can be easily achieved by the use of POM as the molecular-element-regulating platform. MoP/Mo2C@C exhibits more remarkable HER performance over the whole pH range than those of MoP, Mo2C, and the physical mixture of MoP and Mo2C. The low overpotentials of 89, 136, and 75 m...

The development of stable, highly active and cheap electrocatalysts towards the oxygen evolution reaction (OER) has been an ongoing challenge due to practical problems such as slow kinetics and high overpotential. Herein, we utilized a one-pot hydrothermal method to prepare cobalt/nickel molybdate hierarchical microflowers on conductive carbon cloth (MMoO4-CC, M = Co, Ni) as three-dimensional self-supported electrodes for the oxygen evolution reaction. CoMoO4-CC showed better catalytic activity than NiMoO4-CC. Benefiting from the synergistic effect of a large active area, fast charge and mass transport as well as a three-dimensional conducting path, the CoMoO4-CC nanosheet electrode showed a large current density and a relatively low starting potential, delivering 10 mA cm−2 current densities at an overpotential of 290 mV and a Tafel slope of 94 mV dec−1. Furthermore, the CoMoO4-CC nanomaterial shows better electrocatalytic stability than IrO2-CCa, which could be a promising electrocatalyst for large-scale water oxidation.

Carbon nitride (g-C3N4), as a rising star of metal-free photocatalysts, has received considerable attention. However, for practical application, the photocatalytic efficiency of g-C3N4 remains to be further improved. Herein, a series of Keggin-type polyoxoanion (polyoxoanions = SiW12O404−, PW12O403−, PMo12O403−) modified g-C3N4 (POM/C3N4) composites have been successfully prepared. The results of XRD, TEM, XPS and EDAX reveal that a small amount of polyoxoanions was modified on the surface of g-C3N4 with electrostatic and hydrogen bonding interactions. Photocatalytic experiments indicate that these composites exhibit enhanced methyl orange (MO) degradation photocatalytic activity and water splitting H2 production under visible light irradiation. The loading amount and the type of polyoxoanion can tune the photocatalytic performance of the composites. Among these catalysts, 5% SiW12O404− (SiW12)-modified g-C3N4 has the best photocatalytic performance, which is 4.4 times higher than that of pure g-C3N4 for the degradation of MO. The photocatalytic mechanism reveals that polyoxoanions can act as electron traps, which can efficiently promote the separation of photogenerated electrons and holes of C3N4, thus resulting in the enhanced photocatalytic performance of the composites.

The loading of noble-metal nanoparticles (NMNPs) onto various carriers to obtain stable and highly efficient catalysts is currently an important strategy in the development of noble metal (NM)-based catalytic reactions and their applications. We herein report a nanowire supramolecular assembly constructed from the surfactant-encapsulating polyoxometalates (SEPs) CTAB-PW12, which can act as new carriers for NMNPs. In this case, the Ag NPs are loaded onto the SEP nanowire assembly with a narrow size distribution from 5 to 20 nm in diameter; the average size is approximately 10 nm. The Ag NPs on the nanowire assemblies are well stabilized and the over agglomeration of Ag NPs is avoided owing to the existence of well-arranged polyoxometalate (POM) units in the SEP assembly and the hydrophobic surfactant on the surface of the nanowire assembly. Furthermore, the loading amount of the Ag NPs can be adjusted by controlling the concentration of the AgNO3 aqueous solution. The resultant Ag/CTAB-PW12 composite materials exhibit high activity and good stability for the catalytic reduction of 4-nitrophenol (4-NP) with NaBH4 in isopropanol/H2O solution. The NMNPs-loaded SEP nanoassembly may represent a new composite catalyst system for application in NM-based catalysis.

The application of colloidal delivery systems for the encapsulation, protection and increased bioavailability of bioactive ingredients has recently gained increasing interest. The aim of this work was to prepare corn protein hydrolysate-based vitamin D3 (CPH-VD3) nanocomplexes. UV and FT-IR spectra indicated the existence of non-covalent interactions (i.e. hydrogen bonding) between CPH and VD3. The result from X-ray diffraction further suggested the formation of amorphous structure of VD3 after its complexation with CPH. Additionally, dynamic light scattering and transmission electron microscope showed that the CPH-VD3 complexes exhibited a spherical structure with a size scale from 102 to 121 nm. The encapsulation and loading efficiency of VD3 could reach 97% and 9%, respectively. Furthermore, the complexation obviously avoided spontaneous particle aggregation of VD3 against ionic strength ([NaCl] ≤ 200 mmol/L). The remaining ratio of the encapsulated VD3 after exposure to high levels of UV light was as high as 72%. More importantly, in vitro bioaccessibility of VD3 could be up to 95% for the complexes. This study demonstrated that CPH could serve as a novel nano-vehicle for VD3 and it opens up the possibility of using CPH to construct the colloidal delivery system.

OER is the key step to increase the rate of water-splitting reaction. Design and construction of appropriate defects is an effective strategy to enhance catalytic activity. Mn has stronger e−–e− repulsion by the local influence of its 3d orbital electrons. When Mn(III) was successfully introduced into two dimensional F-doped Ni(OH)2, it can tune the surface electronic structure of the F-doped Ni(OH)2 to increase its oxygen deficiency content. In this work, the as-synthesized Mn and F co-doped Ni(OH)2–NF on Ni foam (Mn–F/Ni(OH)2–NF) shows remarkable oxygen evolution performance, exhibiting 233 mV overpotential at 20 mA cm−2, and the Tafel slope is 56.9 mV dec−1 in 1 M KOH. The performance is better than that of the same loading of IrO2 on Ni foam. Density functional theory (DFT) calculations further show that the introduction of oxygen defects can significantly improve the OER catalytic performance of Mn–F/Ni(OH)2–NF.

Accumulation of salts in soils has become a serious environmental threat for plant growth and causes considerable loss in yield. Okra Abelmoschus esculentus L. is an important crop and sensitive to saline stress. In the present study, to explore methods for growing okra in salty area, exogenous gibberellic acid (GA3) and ascorbic acid (AsA) were foliage applied on okra seedling under NaCl stress. The results showed that treatment with 100 mM NaCl decreased shoot length, root length, fresh weight, dry weight, contents of chlorophyll pigments and nutrient elements, enhanced levels of electrolyte leakage, H2O2, lipid peroxidation and activities of antioxidant enzymes. Treatments with 0.1 mM GA3 and/or 0.1 mM AsA could alleviated harmful effects of saline stress on okra seedlings by improving growth indicators, increasing contents of chlorophyll and carotenoids, stimulating activities of antioxidant enzymes and decreasing electrolyte leakage, H2O2 content and lipid peroxidation. Moreover, concentrations of K, Ca, Mg and Fe in leaves and roots as well as levels of osmo-protectants (proline and soluble protein) increased in response to treatment with GA3 + AsA in NaCl-stressed okra seedling. Overall, foliar application of GA3 and/or AsA demonstrated benefits to okra seedlings in salty environments. Combined application of GA3 and AsA was more effective than sole use of GA3 or AsA alone.