Optical properties of ferroic FeO(SeO) and Fe(SeO)·3HO.

Ferroic compounds FeO(SeO) (FSO) and Fe(SeO)·3HO (FSOH) prepared by the hydrothermal method are characterized and their optical properties are investigated by combining with first-principles calculations. The results show that (i) FSO is antiferromagnetic below ∼110 K and becomes ferromagnetic at elevated temperatures, while FSOH is antiferromagnetic at low temperatures probably due to a change in the spin state from Fe ( = 5/2) to Fe ( = 2); (ii) the optical bandgap is determined to be ∼2.83 eV for FSO and ∼2.

Treating waste with waste: Adsorption of anionic dyes in wastewater with surfactant-modified phosphogypsum.

Phosphogypsum (PG) is a solid waste generated during the wet process of phosphoric acid production. The environmental-friendly disposal and recycling of PG is vital in the field of environmental solid waste treatment. In this study, PG is used for adsorbent of dyes in wastewater to achieve the goal of recycling waste with waste.

Surface Reconstruction of CsPbBr Nanocrystals by the Ligand Engineering Approach for Achieving High Quantum Yield and Improved Stability.

Oleylamine/oleic acid (OAm/OA) as the commonly used ligand is indispensable in the synthesis of perovskite nanocrystals (PNCs). Unfortunately, poor colloidal stability and unsatisfactory photoluminescence quantum yield (PLQY) are observed, resulting from a highly dynamic binding nature between ligands. Herein, we adopt a facile hybrid ligand (DDAB/ZnBr) passivation strategy to reconstruct the surface chemistry of CsPbBr NCs.

Constructing Chromium Multioxide Hole-Selective Heterojunction for High-Performance Perovskite Solar Cells.

Perovskite solar cells (PSCs) suffer from significant nonradiative recombination at perovskite/charge transport layer heterojunction, seriously limiting their power conversion efficiencies. Herein, solution-processed chromium multioxide (CrO ) is judiciously selected to construct a MAPbI /CrO /Spiro-OMeTAD hole-selective heterojunction. It is demonstrated that the inserted CrO not only effectively reduces defect sites via redox shuttle at perovskite contact, but also decreases valence band maximum (VBM)-HOMO offset between perovskite and Spiro-OMeTAD.

Rational Construction of a Ni/CoMoO Heterostructure with Strong Ni-O-Co Bonds for Improving Multifunctional Nanozyme Activity.

Due to the lack of a general descriptor to predict the activity of nanomaterials, the current exploration of nanozymes mainly depended on trial-and-error strategies, which hindered the effective design of nanozymes. Here, with the help of a large number of Ni-O-Co bonds at the interface of heterostructures, a prediction descriptor was successfully determined to reveal the double enzyme-like activity mechanisms for Ni/CoMoO. Additionally, DFT calculations revealed that interface engineering could accelerate the catalytic kinetics of the enzyme-like activity.

Activated biochar derived from peanut shells as the electrode materials with excellent performance in Zinc-air battery and supercapacitance.

The use of activated biochar-based electrode derived from waste biomass in energy technologies, such as metal-air batteries and supercapacitors, is an important strategy for realizing energy and environmental sustainability in the future. Herein, peanut shells (waste biomass) were employed to prepare activated biochar materials by pyrolysis in molten KCl and heat-treatment. The effective dispersion and corrosion effects of molten salt for the pyrolysis products during pyrolysis obviously increase defects and specific surface area of the activated biochar materials.

The Evolution of Amitraz and Its Metabolic Degradation Products in Human Blood over 90 Days for Use in Forensic Determination.

Amitraz is a pesticide that is often involved in poisoning cases. In determination process of poisoning cases, a problem often encountered is that when the evidence samples were examined, the poison had already decomposed, thus posing significant difficulty for obtaining evidences. In this study, we qualitatively and quantitatively tracked the metabolic degradation products of amitraz and ascertained that the metabolic degradation products were N,N'-bisdimethylphenylformamidine, N'-(2,4-dimethylphenyl)-N-methylformamidine (DMPF), 2,4-dimethylformamidine (DMF) and 2,4-dimethylaniline (DMA).

3D Graphene-Carbon Nanotube Hybrid Supported Coupled Co-MnO Nanoparticles as Highly Efficient Bifunctional Electrocatalyst for Rechargeable Zn-Air Batteries.

The development of high-efficiency and low-cost catalysts is one of the core and important issues to improve the efficiency of electrochemical reactions on electrodes, and it is also the goal we ultimately pursue in the commercialization of large-scale clean energy technologies, such as metal-air batteries. Herein, a nitrogen-doped graphene oxide (GO)-carbon nanotube (CNT) hybrid network supported coupled Co/MnO nanoparticles (Co/MnO@N-C) catalyst was prepared with a hydrothermal-pyrolysis method. The unique three-dimensional network structure of substrate allowed for the uniform dispersion of Co-MnO nanoparticles in the carbon skeleton.

Determination of capsaicinoids by magnetic solid phase extraction coupled with UPLC-MS/MS for screening of gutter oil.

Capsaicinoids, including capsaicin, dihydrocapsaicin and N-vanillylnonanamide have been identified as characteristic markers for gutter oil. In this study, the nanocomposite of graphene oxide-FeO (GO-FeO) was synthesized by a co-precipitation method, and applied to magnetic solid phase extraction (MSPE) process. The capsaicin, dihydrocapsaicin and N-vanillylnonanamide extracted in gutter oil were analyzed by ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS).

Nitrogen-doped carbon frameworks decorated with palladium nanoparticles for simultaneous electrochemical voltammetric determination of uric acid and dopamine in the presence of ascorbic acid.

A glassy carbon electrode (GCE) was modified with nitrogen-enriched carbon frameworks decorated with palladium nanoparticles (Pd@NCF/GCEs). The modified GCE is shown to be a viable tool for determination of uric acid (UA) and dopamine (DA) in the presence of ascorbic acid (AA). The Pd@NCF was fabricated though one-step pyrolysis and characterized by X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy and nitrogen-adsorption/desorption analysis.

Simultaneous determination of 16 alkaloids in blood by ultrahigh-performance liquid chromatography-tandem mass spectrometry coupled with supported liquid extraction.

Alkaloids are widely present in food and medicine. However, many alkaloids have poisoning effect. Thus, a sensitive and rapid method for determination of alkaloids is highly desired.

Graphene oxide-FeO nanocomposite magnetic solid phase extraction followed by UHPLC-MS/MS for highly sensitive determination of eight psychoactive drugs in urine samples.

Graphene oxide-FeO (GO-FeO) nanocomposite was synthesized by a facile chemical co-precipitation method. The GO-FeO was used as magnetic sorbent to extract the eight psychoactive drugs from urine samples. The analytes are morphine (MOR), 6-monoacetylmorphine (6-MAM), amphetamine (AMP), methamphetamine (MAMP), codeine, cocaine, dolantin and benzoylecgonine (BZE), which were determined by ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS).

A dual-readout nanosensor based on biomass-based C-dots and chitosan@AuNPs with hyaluronic acid for determination of hyaluronidase.

A dual-signal strategy is proposed based on fluorescent biomass-based carbon dots (BC-dots) and chitosan stabilized AuNPs (CS@AuNPs) to determine hyaluronidase (HAase). BC-dots can induce aggregation of CS@AuNPs nanoparticles with a colour change from red to blue. Positively charged CS@AuNPs interacted with the negatively charged hyaluronic acid (HA) through electrostatic adsorption, and CS@AuNPs maintained stability due to the semirigid coil conformation of HA.

CuCoO/N-Doped CNTs loaded with molecularly imprinted polymer for electrochemical sensor: Preparation, characterization and detection of metronidazole.

CuCoO nanoparticles modified with nitrogen doped carbon nanotubes (CuCoO/N-CNTs) have high specific surface area and good electrical conductivity. Herein, a novel electrochemical sensor based on CuCoO/N-CNTs loaded molecularly imprinted polymer (MIP) modified glassy carbon electrode (GCE) is proposed for rapid and ultrasensitive detection of metronidazole (MNZ). The composite of CuCoO/N-CNTs with MIP significantly enhances the electrical signal.

Rose-like Nanocomposite of Fe-Ni Phosphides/Iron Oxide as Efficient Catalyst for Oxygen Evolution Reaction.

In order to accelerate the reaction rate of water splitting, it is of immense importance to develop low-cost, stable and efficient catalysts. In this study, the facile synthesis of a novel rose-like nanocomposite catalyst (Ni P/Fe P/Fe O ) is reported. The synthesis process includes a solvothermal step and a phosphatization step to combine iron oxides and iron-nickel phosphides.

Molecularly imprinted polydopamine modified with nickel nanoparticles wrapped with carbon: fabrication, characterization and electrochemical detection of uric acid.

An electrochemical sensor is described for determination of uric acid (UA). Carbon-enwrapped nickel nanoparticles (Ni@BC) were coated with polydopamine (PDA) that was molecularly imprinted with UA. The biomass carbon (BC) was synthesized by one-step solid-state pyrolysis from leaves of Firmiana platanifolia.

Ultrathin films of a metal-organic framework prepared from 2-methylimidazole, manganese(II) and cobalt(II) with strong oxidase-mimicking activity for colorimetric determination of glutathione and glutathione reductase activity.

Nanosheets (NSs; type ZIF-67) of a metal organic framework (MOF) that was prepared from 2-methylimidazole, manganese(II) and cobalt(II) were obtained by an ultrasonic hydrothermal method. Their Mn(II) doping reached as much as 11.3%.

A fluorometric and colorimetric method for determination of trypsin by exploiting the gold nanocluster-induced aggregation of hemoglobin-coated gold nanoparticles.

A dual-signal assay is described for the determination of trypsin based on the use of gold nanoparticles (AuNPs) that aggregate in the presence of gold nanoclusters (AuNCs) due to electrostatic interaction. This is accompanied by a color change from red to blue. However, if hemoglobin (Hb) is present in the solution, it will attach to the surface of AuNPs, thus preventing aggregation.

A carbon dot-based ratiometric fluorometric and colorimetric method for determination of ascorbic acid and of the activity of ascorbic acid oxidase.

A dual-mode method was developed for the determination of ascorbic acid (AA) and of ascorbic acid oxidase (AA-Ox) activity. It combines the advantages of ratiometric fluorometry and colorimetry. The assay is based on the oxidation of o-phenylenediamine (OPDA) by permanganate (KMnO).

Single-Composition White Light Emission from Dy Doped Sr₂CaWO₆.

A series of Dy ion doped Sr₂CaWO₆ phosphors with double perovskite structure were synthesized by traditional high temperature solid-state method. It was found that there is significant energy transfer between Dy and the host lattice, and the intensities of emission peaks at 449 nm (blue), 499 nm (cyan), 599 nm (orange), 670 nm (red), and 766 nm (infra-red) can be changed by adjusting the concentration of dopant amount of Dy ion in Sr₂CaWO₆. The correlated color temperature of Dy ion doped Sr₂CaWO₆ phosphors can be tuned by adjusting the concentration of Dy ion.

Simultaneous determination of amitraz, chlordimeform, formetanate and metabolites in human blood by liquid chromatography tandem mass spectrometry with phospholipid-removal pretreatment.

In this study, a reliable ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method coupled with an easy, fast and effective sample pretreatment procedure was developed for simultaneous determination of amitraz, chlordimeform, formetanate and their metabolites in human blood. With the procedures of protein precipitation and a phospholipid-removal step, the endogenous compound interference was significantly reduced, and matrix effects were significantly reduced. The linear ranges of matrix-matched standard curves were from 0.

Colorimetric detection of gallic acid based on the enhanced oxidase-like activity of floral-like magnetic Fe O @MnO.

In this study, a colorimetric method was developed for rapid and sensitive determination of gallic acid (GA) by using floral-like magnetic Fe O @MnO composite material with enhanced oxidase-like activity. Fe O @MnO composite material is able to oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to a blue product (oxTMB) with apparent color change and absorbance at 652 nm. GA can reduce the oxTMB yielding a fading blue color.

Colorimetric determination of dopamine by exploiting the enhanced oxidase mimicking activity of hierarchical NiCoS-rGO composites.

A composite consisting of NiCoS and reduced graphene oxide (rGO) was prepared via a hydrothermal process. Compared to individual NiCoS nanomaterials or reduced graphene oxide, the composite exhibits enhanced oxidase-like activity. It is found that dopamine (DA) inhibits the ability of NiCoS-rGO to oxidize the substrate 3,3',5',5'-tetramethylbenzidine (TMB) to form blue colored ox-TMB.

A ratiometric fluorometric and colorimetric probe for the β-thalassemia drug deferiprone based on the use of gold nanoclusters and carbon dots.

A turn-on fluorometric probe is described for the β-thalassemia drug deferiprone (DFP). The probe is making use of carbon dots (C-dots) and gold nanoclusters (AuNCs) which, under 340-nm excitation, display dual emission with peaks at 445 and 592 nm. The orange fluorescence of AuNCs is quenched after the addition of Fe(III), but recovered on addition of DFP.