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In this letter, Bi nanoparticles/reduced graphene oxide (Bi NPs/rGO) composites catalysts were prepared by a simple solvothermal method. The obtained Bi NPs/rGO composites can be used as high-effic...

Photocatalytic CO

Background.This research aims to analyze the clinical characteristics of a novel Corona Virus Disease (COVID-19) registered in the Chinese Clinical Trial Registry (ChiCTR), and to provide an information-based data foundation and information reference for curbing the spread of the COVID-19 epidemic. Methods.The ChiCTR database was comprehensively searched, and the COVID-19 research registration information as of February 24, 2020 was counted. Descriptive analysis of registration time trends and geographical distribution. Chi-square test was used to compare the statistical differences between different study types, intervention methods, research phases and major sponsors. Frequency studies were used to analyze the characteristics of CMT and BI therapy. Results.232 COVID-19 studies registered at the ChiCTR Center were collected. The overall number of COVID-19 registrations was increased. Hubei Province, China has the largest number of registrations, followed by Guangdong, Zhejiang and Sichuan. There were significant differences between the number of participants (P=0.000), study duration (P=0.008), study assignment (P=0.000), and blind method (P=0.000) for different study types. Significant differences could be seen in the dimensions of multicenter study(P=0.022), of participants numbe(P=0.000), study duration(P=0.000) and study assignment(P=0.001) for the four intervention methods. There were significant differences in study assignment (P=0.043) between the early and late studies. CMT drugs with high research frequency are chloroquine, lopinavir / ritonavir, and I-IFN, which are all in phase 4; BI was Cell therapy, plasma therapy, Thymosin, and M/P-AB, which are all in early stages. Conclusion.There were problems of unclear classification of research types and irregular registration behavior. Also, within the studies researched, heterogeneity exists for various dimensions. Different research types, intervention methods, and research stages lead to significant differences in some dimensions of the COVID-19 study. Finally, statistical high-frequency research drugs can provide more treatment options and evidence-based evidence for the clinical practice.

Five molecular complexes with different non-noble metal centers were synthesized. The Co-based complex displays the highest photocatalytic performance for CO

Nitrogen-doped MoS

Copper/nickel nanoparticle-decorated N-doped graphene (Cu/Ni/N-graphene) hybrids were prepared by using a solvothermal method, and further employed as a sensing material for fabricating a sensitive non-enzymatic glucose and ethanol sensor. Compared with Cu, Cu/N-graphene, Ni, Ni/N-graphene, Cu50/Ni50 nanoparticles, and Cu51/Ni49/graphene, the Cu52/Ni48/N-graphene showed enhanced electrochemical activity to glucose and ethanol oxidation, owing to the synergetic effects of Cu and Ni together with N-graphene sheets in the hybrids. The results showed that the Cu52/Ni48/N-graphene hybrid-modified electrode exhibited excellent performance for glucose detection with a wider linear range (from 0.5 μM to 4.6 mM), lower limit of detection (0.2 μM, S/N=3), and higher sensitivity (1847.56 μA mM−1 cm−2) than other modified electrodes. Furthermore, the presented non-enzymatic sensor also displayed a good response toward ethanol oxidation with a wide linear range from 0.2 to 37.1 mM, lower detection limit of 0.1 mM (S/N=3), and faster response time (5 s). These results indicated that the excellent properties could promote the potential application of the bimetals and N-graphene sheets as enhanced materials in constructing non-enzymatic sensors for electrochemical analysis.

In this work, the Cux@Ni100−x core–shell nanoparticles (CSNPs) are deposited on reduced graphene oxide (rGO) sheets, and this nanocomposites (in a Nafion matrix) are shown to be a viable materials for nonenzymatic sensing of glucose. A novel nonenzymatic glucose sensor based on a glass carbon electrode modified with Cu53@Ni47 CSNPs/rGO (referred to as Cu53@Ni47 CSNPs/rGO/GCE) displays an enhanced electrocatalytic activity to glucose oxidation in 0.1 M NaOH solution than that of Cu/GCE, Ni/GCE, Cu/rGO/GCE, Ni/rGO/GCE, and Cu52@Ni48 CSNPs/GCE, respectively. This is attributed to the three-in-one synergetic effects from their bimetallic compositions, specific core–shell structures, and interactions from the bimetallic CSNPs and support materials of rGO sheets. At an applied potential of +0.575 V (vs. SCE), the electrode has a low detection limit (0.5 μM; S/N = 3), a very wide linear range (0.001 mM to 4.1 mM), high sensitivity (780 μA mM−1 cm−2), and a fast response time (3 s). Thus, it has great potential for the development of nonenzymatic glucose sensors.

In this letter, preparation of Co3O4 hierarchical microstructures (HMSs) by the thermolysis of Co-precursor HMSs was described. The Co3O4 HMSs presented high-efficiency catalytic performance in p-n...

A facile surfactant-assisted ion-exchange method has been developed to prepare rhombic dodecahedral Ag3PO4 sub-microcrystals which are ca. 250–600 nm in size through employing uniform Ag2CO3 sub-microrods which are ca. 250–450 nm in diameter and 1–2 μm in length as a precursor for the first time. A series of contrast experiments indicates that the dosages and types of surfactants and different anion sources have a great influence on the formation of the Ag3PO4 rhombic dodecahedra. Based on time-dependent experiments, a reasonable so-called precipitation–dissolution–recrystallization growth mechanism for the Ag3PO4 rhombic dodecahedra has been proposed. The as-prepared sample exhibits higher photocatalytic activity than both commercial TiO2 (P25) and irregular Ag3PO4 particles toward degradation of rhodamine B (RhB) aqueous solution under visible light irradiation. The pseudo-first-order rate constant for RhB photodegradation by the rhombic dodecahedral Ag3PO4 (0.164 min−1) is about 7 and 2.5 times that of P25 and irregular Ag3PO4, respectively.

Wire-like and flower-like cerium ion (Ce3+)-doped neodymium phosphate nanostructures (NdPO4:Ce3+ NSs) were synthesised via a direct precipitation process at room temperature. The different reaction conditions such as the phosphate anion source, solvent, and surfactant were carried out to discuss the influence for the morphologies and photoluminescence (PL) properties. Experimental results showed that the surfactants of dodecyl benzene sulphonic acid sodium and dodecyl sulphonic acid sodium play an important role in controlling the flower-like NdPO4:Ce3+ NSs. The flower-like NdPO4:Ce3+NSs exhibited higher PL property than that of wire-like NdPO4:Ce3+NSs.

Up-to-date information on the current progress made in the research and development to control the global COVID-19 pandemic is important. The study aimed to analyze the clinical trial characteristics and vaccine development progress of the new Coronavirus Disease 2019 (COVID-19) registered with the World Health Organization International Clinical Trial Registry Platform (WHO ICTRP).A comprehensive search of COVID-19 clinical trials since the establishment of the ICTRP to June 11, 2020, was conducted to record and analyze relevant characteristics. Chi-Squared test was used to compare the statistical differences between different research types, interventions, and sources.A total of 3282 COVID-19 clinical trials in 17 clinical trial registration centers were registered with the WHO ICTRP. The main research sources for the present study were ClinicalTrials.gov and ChiCTR. There were significant differences in the parameters of study location (P = .000), number of participants (P = .000), study duration (P = .001), research stage (P = .000), randomization procedure (P = .000), and blinding method (P = .000) between the 2 registration sources. There were significant differences in all the parameters between different kinds of intervention methods. Hydroxychloroquine, plasma therapy, and Xiyanping injection were the high-frequency research drugs used. Ten different vaccine studies were registered under phases I-II.Amongst the studies researched, heterogeneity existed for various parameters. Differences in the type of study, interventions, and registration sources of the studies led to significant differences in certain parameters of the COVID-19 clinical trials. The statistics of high-frequency drugs and the progress of vaccine trials may provide an informative reference for the prevention and control of COVID-19.

Nitrogen-doped MoS2 quantum dots (N-MoS2 QDs) were synthesized via a facile hydrothermal approach, and exhibited high fluorescence quantum yield (QY, 14.9%), excellent photostability, biocompatibility and water solubility. A novel method with good selectivity and sensitivity was established to assay hematin using N-MoS2 QDs as a fluorescent probe based on inner filter effect (IFE). Fluorescent quenching of N-MoS2 QDs has a fine linear dependence with the concentration of hematin in the range of 0.5–15 μmol/L and a limit of detection of 0.32 μmol/L (S/N = 3). By the detection method, average concentration of hematin in real health human erythrocytes was measured as 22.5 ± 3.9 μmol/L. And, recoveries range varied from 94 to 108% through standard recovery experiment. The N-MoS2 QDs probe shows excellent photostability, low cytotoxicity and anti-interference ability for hematin assay, which may become a promising method for the test of hematin in human blood.

In this letter, a high-efficiency and magnetically recoverable catalysts of novel Fe36Co64 alloy microstructures (AMSs) with 3D spicate shapes were synthesized by solvothermal method. The 3D spicate Fe36Co64 AMSs displayed a high saturation magnetization (163.5 emu/g) and exhibited soft magnetic behavior. The obtained 3D spicate Fe36Co64 AMSs were used as cyclicity and magnetically recyclable catalysts for catalytic hydrogenation of p-nitrophenol into p-aminophenol.

(CoxNi1−x)0.85Se nanostructures (NSs) with different shapes (i.e., sheet-like, flower-like, and urchin-like) were synthesized by a sacrificial template method. As far as we know, this paper may be the first work that used (CoxNi1−x)0.85Se NSs as catalysts for reduction of 4-nitrophenol (4-NP) by NaBH4 in aqueous solution.

A facile and effective solution phase reduction method was developed to synthesize graphene-based magnetic metal nanocomposites. Metals (Co, and Ni) or alloys (Fe51Co49, Fe48Ni52, Ni49Co51, Co51Cu49, and Ni52Cu48)/reduced graphene oxide (RGO) nanocomposites were successfully prepared by reduction of the corresponding aqueous metal ions and ethylenediamine (EDA)–graphene oxide (GO) with hydrazine hydrate at 353 K for 1 h under N2 atmosphere. The effects of synthetic parameters such as metal ions concentration, adding sequence of NaOH and N2H4·H2O, linkage agent and reaction time on the formation of nanocomposites were investigated. The experimental results showed that using ethylenediamine and adding sequence played critical roles in the formation of metals or alloys/RGO nanocomposites. Magnetic hysteresis measurements revealed that the as-synthesized metals or alloys in nanocomposites showed excellent soft magnetic behavior with enhanced saturation magnetization, and could have promising applications in biotechnology, catalysis, and magnetic storage devices.

Nitrogen-doped graphene modified AgX@Ag (NG–AgX@Ag, X = Br, Cl) composites were prepared by a simple co-precipitation method under ambient condition. The composites possessed higher photocatalytic activity than corresponding bare AgX@Ag and TiO 2 –AgX@Ag towards degradation of rhodamine B (RhB) aqueous solution under visible light irradiation, which can be ascribed to the corporative effects of more light harvest, enhanced adsorption capacity and more efficient separation of photogenerated electron–hole pairs after integrated with nitrogen-doped graphene. The NG–AgX@Ag (X = Br, Cl) composites exhibited efficiencies of 86% and 89% for photodegradation of RhB, which were about 2 times and 1.8 times of corresponding bare AgX@Ag (X = Br, Cl), respectively. The composites also had a relatively high stability.

A series of nitrogen-doped graphene – BiOBr (NG – BiOBr) nanocomposites with different weight addition ratios of nitrogen-doped graphene were firstly prepared by a facile solvothermal method, and found to possess a higher photocatalytic activity than pure BiOBr toward degradation of methyl orange in water under visible light irradiation. The NG – BiOBr composite with 1.76 wt% NG content exhibited the highest photodegradation efficiency of methyl orange, its degradation rate was about 50, 4.6 and 3.8 times of P25, BiOBr microsphere and 1.76 wt% RGO–BiOBr composite, respectively. The enhanced photocatalytic performance could be ascribed to more visible light harvest and more effective separation of photo-generated electron–hole pairs.

Highly uniform Ag 3 PO 4 nanorods with different sizes were fabricated by an easy chemical deposition process onto polycarbonate (PC) template. The average diameters of the synthesized nanorods were ~2.0 μm, 275 nm, or ~85 nm using PC membrane with different pore sizes. The morphologies, structures, compositions, and photocatalysis tests of the as-prepared Ag 3 PO 4 nanorods were studied in detail. Results indicated that the nanorods had high photocatalytic efficiency for the photodegradation of rhodamine B , methylene blue, and Congo Red under visible-light irradiation. Only the nanorods with a mezzo diameter (275 nm) showed the best photocatalytic activity because of the combined effects of their morphology and size.

A series of nitrogen-doped graphene–ZnO (NG–ZnO) nanocomposites with different weight addition ratios of nitrogen-doped graphene have been prepared via a facile sol–gel method. ZnO nanoparticles (NPs) in diameter of 8–20 nm were distributed on the surface of NG, which exhibit higher photocatalytic activity, recyclability and stability than ZnO NPs toward degradation of methyl orange in water under ultraviolet light irradiation. The ZnO NPs with 2 wt% NG content exhibited the highest photodegradation efficiency of methyl orange (96.4% in 15 min), which was about 1.23 times of pure ZnO NPs (78.2% in 15 min).

A visible-light sensitive Ag 2 SO 3 semiconductor photocatalyst with size of ca. 500 nm was prepared by a simple precipitation method. This photocatalyst exhibits high-efficiency degradation ability for typical three dyes, which can be ascribed to the efficient photosensitised electron injection and slow electron recombination. The photocatalytic reaction follows a pseudo-first-order reaction and the rate constant of Ag 2 SO 3 for the degradation of rhodamine B is estimated to be 1.7 times that of commercial TiO 2 . The stability of unstable Ag 2 SO 3 was remarkably enhanced by the addition of Na 2 SO 3 . The h + and ·O 2 - played relatively major roles during the photocatalytic reaction.

Ag 3 PO 4 nanoparticles with 50–100 nm in size distributed on the surface of ZnO nanorods with ca. 20 nm in diameter and 1–2 μm in length have been synthesized by a facile method. The Ag 3 PO 4 –ZnO nanorod composites had much higher photocatalytic activity toward degradation of Rhodamine B (RhB) under visible light irradiation than pure ZnO nanorods, and had better recyclability and stability than pure Ag 3 PO 4 nanoparticles. The Ag 3 PO 4 –ZnO nanorod composite with the molar ratio of Ag 3 PO 4 :ZnO = 1:40 exhibited the highest photodegradation efficiency of RhB (93%), which was 1.5 times of pure ZnO nanorods.

Graphene oxide–Ag2CO3 (GO–Ag2CO3) composites have been prepared by a simple and effective precipitation method, and found to exhibit a higher photocatalytic activity toward degradation of organic dyes, including rhodamine B, methylene blue and methyl orange, in aqueous solution, than pure Ag2CO3 crystal under visible light. The Ag2CO3 crystal with 0.9 wt% GO content exhibited the highest photodegradation efficiency for organic dyes, which was 2 times that of pure Ag2CO3 crystal. The improved photocatalytic activity of GO–Ag2CO3 composites was attributed to the corporative effects of high-surface-area of GO sheets, enhanced absorption of organic dyes, small band gap, more efficient separation of photogenerated electron–hole pairs, and good electron acceptor properties of GO. The photocorrosion of Ag2CO3 crystal can be efficiently inhibited by GO, since the transfer of photogenerated electrons from the surface of Ag2CO3 crystal to GO sheets can reduce the possibility of decomposing Ag+ to Ag0, which resulted in an improved stability and recyclability of the GO–Ag2CO3 composite in the photocatalytic reaction. This facile and straightforward method has promising applications in the fabrication of different graphene oxide-based heterostructure photocatalysts.

A series of reduced graphene oxide—flower-like BiOCOOH (RGO–BiOCOOH) composites with different weight addition ratios of reduced graphene oxide have been prepared for the first time by a two-step solvothermal approach, which showed higher photocatalytic activity than BiOCOOH toward degradation of rhodamine B (RhB) in water under simulated sunlight irradiation. The RGO–BiOCOOH composite with 2 wt% RGO content exhibited the highest photocatalytic degradation efficiency of RhB, which was about 2 times of pure BiOCOOH microflower. The enhanced photocatalytic activity of RGO–BiOCOOH composite could be attributed to the synergetic effects of enhanced adsorption capacity, narrower band gap, and more efficient separation of photogenerated electron–hole pairs and effective interfacial hybridization between RGO and flower-like BiOCOOH architecture.

Ag3PO4–Bi2O2CO3 composites were prepared by a combination of hydrothermal technique and precipitation method for the first time. Ag3PO4 nanoparticles with ca. 200 nm in size were attached to the surface of Bi2O2CO3 microspheres in diameter of 1–2 μm, which had higher photocatalytic activity than Bi2O2CO3 microspheres toward degradation of Rhodamine B (RhB) in water under visible light irradiation. The Ag3PO4–Bi2O2CO3 composite with the molar ratio of Ag3PO4:Bi2O2CO3=1:1 exhibited the highest photodegradation efficiency of RhB (97% in 30 min), which was about 2.2 times of pure Bi2O2CO3 microspheres. The enhanced photoactivity could be ascribed to more light harvest and more effective separation of photo-generated electron–hole pairs.

A series of nitrogen-doped graphene–Ag 2 CO 3 (NG–Ag 2 CO 3 ) composites with different weight addition ratios of NG as a visible-light-induced photocatalyst were fabricated through a facile precipitation method. It was found that NG–Ag 2 CO 3 composite with a proper addition amount of NG exhibited higher photocatalytic activity and improved anti-photocorrosion than Ag 2 CO 3 toward degradation of rhodamine B (RhB) in water under visible light irradiation. The rodlike Ag 2 CO 3 sub-microcrystals with 4.5 wt% NG content exhibited the highest photodegradation efficiency of RhB (92% in 60 min), which was about 1.2 times of pure Ag 2 CO 3 sub-microcrystals (76% in 60 min). The improved photocatalytic performance could be ascribed to the enhanced visible light absorption efficiency and more effective separation of photo-generated electron–hole pairs.

Ni0.85Se plate-like nanostructures (PNSs) had been prepared by a template method, and by a similar process, the Ni0.85Se nanoparticles were obtained by using NiCl2·6H2O as the nickel source. The Ni...

In this reported work Ni-riched NiO-Co3O4 sheet-like nanocomposites (SNCs) were obtained through a facile solvothermal method in a mixed solvent and subsequently calcinated in air. Galvanostatic charge-discharge measurement revealed that the Ni-riched NiO-Co3O4 SNCs electrode has an impressive specific capacitance as high as 836 F g−1 at 4 A g−1 in 3 M KOH solution. The as-obtained Ni-riched NiO-Co3O4 SNCs product showed a weak cycling stability, but the higher capacitance (424 F g−1) was retained after 1000 cycles at 4 A g−1.

Uniform octahedral zinc tetraphenylporphyrin (ZnTPP) microcrystals were obtained in a large scale by a facile, fast and surfactant-free process at room temperature. The effects of synthetic parameters such as solvent and concentration on the formation and morphology of ZnTPP were investigated. Furthermore, by varying the reaction time, both the morphology and the size of the ZnTPP microcrystals can be controlled.

The dinuclear complex [Cu2(HL)2(H2O)2](ClO4)2 (1) [H2L = 5′-(pyridin-2-yl)-1-H,2′-H-3, 3′-bis(1, 2,4-triazole)] was obtained and fully characterized. It exhibits a centrosymmetry configuration, in which each copper(II) ion is pentacoordinate with four nitrogen atoms of two triazole ligands and one oxygen atom from a water molecule. The net atomic charges distribution and atomic orbital contribution to frontier molecular orbitals were obtained using the Gaussian 98 program with Hartree-Fock method at LANL2DZ level, indicating that the copper(II) ion has the potential to accept the electron of O2·–. The complex showed quasi-reversible one-electron CuII/CuI redox waves with redox potentials of –0.034 V. The SOD-like activity (IC50) of 1 was measured to be 0.18 ± 0.01 μM by xanthine/xanthine oxidase-NBT assay at pH 7.8. The relatively high SOD activity suggests that the positive charge of protonated triazole can effectively steer O2·– to and from the active copper ion.

A new ruthenium complex containing bidentate xanthate ligands was synthesized in a good yield. This complex was characterized by elemental analysis, proton nuclear magnetic resonance(1H NMR), Fourier transform infrared(FTIR) and UV-Vis spectroscopies. The cyclic voltammetry of the complex revealed one quasi-redox wave centered at Ru(III)/ Ru(II) couple, indicating its catalytic potential. So the preparation of a glass carbon electrode modified with ruthenium xanthate complex and its electrocatalytic activity toward the oxidation of tryptophan(Trp) were also studied. The experimental results show that the modified electrode had excellent electrocatalytic activity for the oxidation of tryptophan. Moreover, under the optimized conditions, the oxidation peak current was proportional to tryptophan concentration in a range of 2.5×10−7 to 5.0×10−5 mol/L with a correlation coefficient of 0.9928 and a detection limit of 8.3×10−8 mol/L(S/N=3). Using the proposed method, tryptophan was successfully determined in pharmaceutical samples with standard addition method.

In this Letter, the catalytic activities of dendritic and flowerlike Ni–Co alloy microstructures (AMs) are evaluated by using a model reaction based on the reducing of 4-nitrophenol (4-NP) to 4-amitrophenol by NaBH4. The activation energy, the entropy of activation and the pre-exponential factor for each type of Ni–Co AMs were determined, based on the average reaction rate constants at three different temperatures. The kinetic data indicate that dendritic Ni33.0Co67.0 AMs were catalytically more active than flowerlike Ni32.7Co67.3 AMs probably due to their having more surface-to-volume ratio and surface areas under the nearly same sizes, since the Brunauer–Emmett–Teller surface areas were determined as 33.21 m2/g for dendritic Ni33.0Co67.0 AMs and 21.06 m2/g for the flowerlike Ni32.7Co67.3 AMs, respectively. Excitingly, the NiCo2 AMs showed good catalytic activities in reduction of 4-NP, which revealed potential application in catalytic reduction of aromatic nitro compounds by NaBH4.

Crystalline FeCo alloys (Fe 64 Co 36 , Fe 59 Co 41 , and Fe 37 Co 63 ,) nanoparticles in diameter of 5–12 nm were synthesized by reduction of FeCl 3 and CoCl 2 with hydrazine under ultrasonic wave, which is a simple, low-cost, surfactant-free route, and may stimulate technological interests. As-synthesized Fe 59 Co 41 nanocrystallite shows excellent soft magnetic behavior with high saturation magnetization up to 216.2 emu/g that is comparable with that of bulk Fe and Fe 60 Co 40 alloy, and could have applications in catalysis, biotechnology, and magnetic storage devices.

In order to study the sorption characteristics of Zr–Co–RE (RE indicating rare earth element) thin films, Zr–Co–RE films were prepared by RF magnetron sputtering from an alloy target. Sorption characteristics depending on layered structures, activation procedures and substrate roughness were investigated. The studies reveal that Zr–Co–RE films can be activated at low temperature with the modification of microstructures. Tri-layered films exhibit more favorable sorption capability than the single-layered film. Sorption properties can be improved by optimizing activation parameters (time or temperature) and deposition on coarse substrates. Rough films with larger specific surface area exhibit extremely sustainable sorption speed and large sorption capacity. The sorption capacity of Zr–Co–RE rough film was also calculated by the fitting formula between sorption speed and sorption quantity.

Four novel [60]fullerene pyrrolidines containing trifluoromethyl (CF3) group have been synthesized via 1,3-dipolar cycloaddition reaction, which have been characterized by UV-Vis spectroscopy, fourier transform infrared spectroscopy, matrix-assisted laser desorption ionization-time of flight mass spectroscopy, and 1H, 13C, 19F nuclear magnetic resonance spectrometer (1H NMR, 13C NMR, 19F NMR). Their optical and electrochemical properties have been studied, and the results show that those fulleropyrrolidines containing CF3 group have good fluorescence and electrochemical properties. Compared with C60, they have negative shifts in varying degrees for half-wave potentials, and may have potential applications for photovoltaic conversion materials since their lowest unoccupied molecular orbital (LUMO) levels are close to that of [6,6]-phenyl-C61-butyric acid methyl ester.

A simple, fast and accurate chemiluminescence (CL) method for the determination of sulphite has been developed, based on its sensitizing effect on the CL reaction between a novel water-soluble iridium complex, [(dpci)2Ir(bvbbi)](PF6) (dpci = 3,4-diphenylcinnoline; bvbbi = N,N′-bivinylester-1H,1′H-[2,2′] bibenzimidazole) and cerium(IV). Under the optimal experimental conditions, the increased CL response was linear, with the concentration of sulphite over the range 5.0 × 10–7–5.0 × 10–4 mol/L. The detection limit of the method was 1.6 × 10–7 mol/L, with a relative standard deviation (RSD) of 2.7% for nine repetitive determination of 1.0 × 10–4 mol/L sulphite. The method was successfully applied to the quantitative analysis of sulphite in sugar samples. The possible reaction mechanism of sulphite on the [(dpci)2Ir(bvbbi)](PF6)–cerium(IV) system is also briefly discussed. Copyright © 2012 John Wiley & Sons, Ltd.

Dendritic Ni33.8Co66.2 alloy microstructures with hexagonal closed-packed phase have been prepared in large-scale by a simple and facile solution phase chemical route, while flowerlike Ni33.4Co66.6 in size of 2.5–5.5 μm was synthesized by solvothermal routes. Experimental results show that the reaction temperature, total concentration of [Ni2+] + [Co2+], and kinds of solvent and surfactants are key factors for controlling the morphology and crystal phase of the NiCo alloy. The possible formation mechanism for the Ni33.8Co66.2 dendrites has been discussed. Magnetic measurements revealed that both of the NiCo2 alloys obtained are ferromagnetic at room temperature. The saturation magnetization value of the Ni33.8Co66.2 dendrites (163.55 emu/g) is lower than that of the flowerlike Ni33.4Co66.6 (195.79 emu/g), but the Ni33.8Co66.2 dendritic structures exhibit an enhanced coercivity value. NiCo2 alloys with different shapes (Ni33.8Co66.2 dendrites and flowerlike Ni33.4Co66.6) have been used as reusable heteroge...

Bi2S3 nanowire/CdS nanoparticle heterostructure has been designed and constructed through an easy wet-chemistry approach at 140 °C for 8 h. The product is mainly composed of Bi2S3 nanowires, several hundred nanometers long and 10 nm wide, and epitaxially grown triangle-like CdS nanoparticles with size of 20 nm at their surfaces. A possible sequential deposition growth mechanism is proposed on the basis of experimental results to reveal the formation of the nanoscale heterostructure. Under the irradiation of UV light, the as-prepared nanoscale Bi2S3/CdS heterostructure exhibits enhanced photochemical efficiency that can be mainly attributed to the microstructure of the product. In the nanoscale heterostructure, the CdS nanoparticle not only determines the overall band gap energy, but also controls the charge carrier transition, recombination, and separation, while the Bi2S3 nanowire serves as support for the CdS nanoparticle, defines the specific surface area of the product and thus influences the photocat...

By taking advantage of the redox potential differences between substrate and the metal ions (Mm+/M), and the excellent conductivity of graphene sheets, a versatile platform, electroless deposition, is used for the synthesis of metal (M)-graphene hybrid materials (MAg, Au, Pd, Pt and Cu) by immersing graphene sheets coated on metal (Cu or Zn) foils into solutions containing the corresponding precursors, which have higher redox potentials than that of Cu or Zn foil. The size and density of the metal nanoparticles on the graphene sheet surface can be controlled by rationally designing of the experiments. Stacks of metal-decorated graphenes were obtained by repeating the processes of graphene-coating and metal-depositing. Pt-graphene hybrid materials have shown good electrocatalytic activity toward methanol oxidation.

Uniform 3-D flower-like NiCo crystalline nano/microstructures were synthesized by a surfactant-assisted solvothermal process at 120 °C for 10–15 h, which were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), energy dispersive X-ray spectroscopy (EDX) and vibrating sample magnetometry (VSM). The effects of synthetic parameters such as surfactant, solvent and molar ratio of metal ions on the formation and morphology of NiCo samples were investigated. The experimental results showed that sodium dodecylbenzenesulfonate (SDBS) and solvent ethanol play critical roles in the formation of novel flower-like NiCo alloy assemblies, and the self-assembly evolution was found to be a two-stage growth process. Magnetic hysteresis measurements revealed that the flower-like Ni48Co52 alloy spheres with an average diameter of ca. 800 nm and hierarchical flower-like Ni47Co53 alloys with a size of ca. 5 μm display ferromagnetic behaviors with saturation magnetizations of 111.33 emu g−1 and 103.58 emu g−1, and coercivities of 84.27 Oe and 52.71 Oe, respectively, at room temperature.

In this study, CoNi2S4 microstructures (CoNi2S4 MSs) with urchin-like and flower-like shapes were synthesized by a sacrificial template method based on the Kirkendall effect. The as-prepared CoNi2S...