One-step Hydrothermal Method Research Articles

Synthesis and Characterization of Copper-Crosslinked Carbon Dot Nanoassemblies for Efficient Macrophage Manipulation.

Nanomedicines loaded in macrophages (MAs) can actively target tumors without dominantly relying on the enhanced permeability and retention (EPR) effect, making them effective for treating EPR-deficient malignancies. Herein, copper-crosslinked carbon dot clusters (CDCs) are synthesized with both photodynamic and chemodynamic functions to manipulate MAs, aiming to direct the MA-mediated tumor targeting. First, green fluorescent CDs (g-CDs) are prepared by a one-step hydrothermal method. Subsequently, the g-CDs are complexed with divalent copper ions to form copper-crosslinked CDCs (g-CDCs/Cu), which are incubated with MAs for their manipulation. Experimental results revealed that the prepared g-CDCs/Cu displayed good aqueous dispersibility and fluorescent emission properties. The nanoassemblies can be activated to deplete the overexpressed glutathione (GSH) and generate reactive oxygen species (ROS) in the presence of laser irradiation through the combined Cu-mediated chemodynamic therapy and CD-mediated photodynamic therapy. Furthermore, the ROS produced in MAs enabled polarization of MAs to antitumor M1 phenotype, suggesting the future potential use to reverse the immunosuppressive tumor microenvironment. These results obtained from the current study suggest a significant potential to develop g-CDCs/Cu for GSH depletion, ROS generation, and MA M1 polarization as a theransotic agent to tackle cancer.

Facile synthesis of N-doped graphene quantum dots as a fluorescent sensor for Cr(vi) and folic acid detection.

The development of stable fluorescent sensors for toxic pollutants and drugs is meaningful to the environment and public health. In this work, nitrogen-doped graphene quantum dots (N-GQDs) were facially synthesized by a one-step hydrothermal method using soluble starch and l-arginine as carbon and nitrogen sources in pure water at 190 °C for 4 h. The as-synthesized N-GQDs were well characterized and displayed blue fluorescence emission at 445 nm with excellent pH stability, salt tolerance, thermostability, photobleaching resistance and reproducibility. Moreover, N-GQDs could serve as an "on-off" sensor for selective detection of Cr(vi) and folic acid with low detection limit (0.80 and 2.1 μM), good linear correlation over wide linear range (0-50 μM and 0-200 μM) as well as short response time (<10 s). The practical applications of N-GQDs for Cr(vi) and folic acid detection in actual samples were further investigated and showed acceptable recoveries (92-105%) with relative standard deviations less than 5%. These results indicated that this N-GQDs-based sensor could be a potential alternative for Cr(vi) and folic acid detection in the fields of environmental monitoring and drug analysis.

Facile Synthesis of Ni(OH)2 through Low-Temperature N-Doping for Efficient Hydrogen Evolution

Nickel hydroxide is a potentially cheap non-precious metal catalytic material for alkaline hydrogen evolution reactions (HERs). Herein, a nickel form (NF)-based nitrogen-modified nickel hydroxide (N-Ni(OH)2/NF) with interlaced two-dimensional (2D) nanosheet structures was synthesized by a simple one-step ammonia vapor-phase hydrothermal method for efficient electrocatalytic HERs. The effect of the reaction temperature of the catalyst preparation on the HERs’ performance was studied in detail. The HER activity of N-Ni(OH)2/NF is enhanced by the large specific surface area, mass transfer and electron conductivity provided by a unique and suitable 2D nanostructure and nitrogen doping. The obtained N-Ni(OH)2/NF not only shows a superior HERs performance, but also exhibits good stability during long-term electrolysis.

Zr and Mo doping to modulate the electronic structure of Ni3S2 for OER electrocatalysis

To enter the era of a clean and sustainable hydrogen economy, it is crucial to first discover non-precious metal electrocatalysts that can be used for oxygen evolution reaction (OER) in electrochemical water splitting. In this work, highly active and durable Zr and Mo co-doped Ni3S2 catalyst (ZrMo–Ni3S2/NF) loaded on Ni foams for OER in alkaline media were prepared using a simple one-step hydrothermal method. The resulting nanocomposites were characterized by various methods and evaluated for their electrocatalytic performance towards OER. The ZrMo–Ni3S2/NF nanocomposite exhibites excellent OER electrocatalytic activity with a low overpotential of 257 mV at a current density of 10 mA cm−2 as well as an excellent electrochemical stability, showing only a slight decay during the 70 h test period. The remarkable electrocatalytic performance of the ZrMo–Ni3S2/NF electrode is attributed to the synergistic strong electronic interaction between the co-doped Zr and Mo. This work not only demonstrates a highly electrocatalytic active OER catalyst for water splitting, but also provides a new perspective on the development of highly active OER catalysts through doping strategies.

Hydrothermal synthesis of SnO2/MoO3-x/rGO ternary nanocomposites as a high-performance anode for lithium ion batteries

The theoretical specific capacity of tin dioxide (SnO2) as a lithium-ion batteries (LIBs) anode material is up to 1494 mAh·g−1, far exceeding that of graphite. However, the low conductivity, volume expansion, crushing failure and particles agglomeration during charge/discharge cycles limit its application in LIBs. In this work, the SnO2/MoO3-x/rGO composite material was synthesized by one-step hydrothermal method, with SnO2 and amorphous MoO3-x tightly and uniformly anchored at the surface of reduced graphene oxide (rGO). The results of structural characterization and electrochemical performance evaluation show that amorphous MoO3-x can increase the reactive active sites, inhibit Sn particles aggregation, and promote the reversible reaction of SnO2. rGO effectively improves the electrical conductivity of the composite and buffers the volume change of Li-Sn alloying/dealloying during cycles. In addition, due to introduction of MoO3-x and rGO a stable SEI film can be formed at the material's surface to improve the cycle stability. SnO2/MoO3-x/rGO exhibits excellent rate performance and cycle performance. When the rGO content is 10.9 wt%, the reversible capacity of the composite reach 813 mAh·g−1 after 800 cycles at current density of 1.0 A·g−1, and 450.6 mAh·g−1 after 1000 cycles at current density of 5.0 A·g−1, with the capacity retention rate of 96.9%.

Three-dimensional MoS2 nanosheets embeded within NiTe nanorods forming semicoherent heterojunctions achieving high-performance potassium-ion batteries

Three-dimensional MoS2 nanosheets uniformly embedded within NiTe nanorods are synthesized via one-step hydrothermal method and subsequently coated with a carbon layer to form stable NiTe@MoS2@C heterojunctions. The heterojunctions exhibit moderate lattice mismatch (δ =20.0 %), strong electric fields, and uniform carbon shells, resulting in unique electronic configurations and abundant active sites. As an anode for potassium-ion batteries, NiTe@MoS2@C demonstrated an high reversible capacity of 258.4 mAh g−1 after 100 cycles at a rate of 200 mA g−1. Moreover, it showed a stable reversible capacity of 177.5 mAh g−1 at a high rate of 5000 mA g−1, indicating excellent rate performance. Notably, even in the NiTe@MoS2@C//perylene tetracarboxylic dianhydride full battery configuration, a significant reversible capacity of 87.4 mAh g−1 was maintained after 100 cycles at a rate of 200 mA g−1, manifesting its remarkable potential for practical applications in potassium-ion batteries. Theoretical calculations further revealed that the well-designed NiTe@MoS2 heterojunction significantly enhances K+ ion diffusion.

Preparation of Fluorescent "on-off-on" Carbon Quantum Dots and Their Application to the Detection of Fe3+ and Ascorbic Acid and Information Encryption.

Carbon quantum dots are a new type of fluorescent carbon-based nanomaterials, and their excellent properties have provoked a strong research interest. Herein, blue-fluorescent carbon quantum dots (k-CQDs) were successfully synthesized by a simple one-step hydrothermal method using chitosan and ethylenediaminetetraacetic acid as precursors. It was found that Fe3+ could quench the fluorescence of k-CQDs by a dynamic quenching mechanism that increased the positive charge in solution. Due to ascorbic acid (AA) can reduce Fe3+ to Fe2+, the positive charge in solution was reduced and the fluorescence of k-CQDs was restored. Based on the mechanism of the fluorescence "on-off-on", k-CQDs were used for the detection of Fe3+ and AA with strong antijamming capability. The LOD for Fe3+ concentrations in the ranges of 0 to 30 µM and 30 to 100 µM were 0.3 µM and 0.76 µM, respectively. The LOD for AA concentrations in the ranges of 0 to 82.5 µM and 82.5 to 172.5 µM were 3.93 µM and 1.63 µM, respectively. Spiking recoveries of Fe3+ in tap water, AA in orange juice and tomato juice were 87.93 ∼ 101.13%, 86.77 ∼ 105.15% and 86.43 ∼ 103.80%, respectively. Meanwhile, k-CQDs also showed good potential for anti-counterfeiting encryption.

A nanoflower structure rare-earth La3+ doping Sn3O4 with highly catalytic active interfaces as a sulfur host facilitates the conversion kinetics of polysulfides in high-performance lithium-sulfur batteries

Lithium-sulfur batteries are considered a favourable contender for next-generation energy storage systems owing to their high energy density (2600 Wh·kg−1). However, the severe "shuttle effect" of polysulfides and the slow redox kinetics involving phase transitions have seriously limited the commercialization of lithium-sulfur batteries. On this basis, in this paper, a type of nanoflower structure rare-earth lanthanum ion (La3+) doping Sn3O4 with a large number of catalytic active interfaces is designed via a facile one-step hydrothermal method. When serves as a capture centre to immobilize polysulfides, it exhibits a strong chemical adsorption capacity. Moreover, due to the unique 4 f electron configuration of the rare-earth elements, nanoflower structure La3+ doping Sn3O4 (La@Sn3O4) as sulfur-wrapped matrix has a strong catalytic activity, which can effectively accelerate the conversion process of polysulfides. At the same time, the catalytic mechanism of La@Sn3O4/S composite cathode material targeting the solid to liquid phase transformation of polysulfides is effectively revealed via in-situ Raman spectroscopy test and the initial discharge capacity can reach 1429.6 mAh·g−1 at a current density of 0.1 C, and the capacity retention rate is 76.5 % after 130 cycles.

Fe-doped herbal medicine-based carbon dots nanozyme as safe and effective antimicrobial and wound healing agent

Bacterial infections pose a serious worldwide public health concern and play an important role in slowing or dramatically delaying wound healing. However, traditional antibiotics are faced with obstacles such as bacterial resistance and unsatisfactory biocompatibility, which has impeded further clinical translation. In recent years, antimicrobial nanomaterials have emerged as viable alternatives for combating bacterial infections, and carbon dots (CDs) have received particularly widespread attention due to their superior characteristics. In this work, a simple and eco-friendly one-step hydrothermal method was employed using the natural herbal medicine Eucommia ulmoides as a biomass carbon source to synthesize an Fe-doped CDs nanozyme (Fe-CDs) with good peroxidase-like (POD-like) activity, high biocompatibility, and strong antimicrobial activity for safe and effective antimicrobial therapy and the promotion of wound healing. L929 cells co-cultured with Fe-CDs did not show significant cytotoxicity and favored cell proliferation at appropriate concentrations. In addition, Fe-CDs catalyzed the decomposition of low-concentration H2O2 to ·OH, leading to enhanced antimicrobial activity. Both in vitro and in vivo experiments demonstrated that Fe-CDs exhibit potent antibacterial properties, the ability to promote cell migration and angiogenesis, and significant potential for promoting the healing of infected wounds. In summary, a green and safe antimicrobial nanozyme based on a biomass herbal medicine was developed in this work, offering promising insight into the development of novel antimicrobial materials and tissue regeneration engineering.

Recycling Process of Spent Alkaline and Zn-C Batteries for the Re-Utilization in Rechargeable Zn-Ion Battery

The Zn, Mn and C extraction processes from spent primary batteries and the synthesis of recycled Zn film, MnO2 and MnO2/C for Zn-ion battery application were developed in the project. The Zn, Mn and C extraction process involved the acid leaching of Zn and Mn ions from the spent alkaline and Zn-C battery electrodes in the lab-scale was initially investigated using various leaching conditions. The acid leaching using 0.5-2 M HCl and H2SO4 at ambient temperature providing Zn extraction efficiencies in a range of 72.3-95.3%. By introducing an inexpensive reducing agent namely sodium sulfide (Na2S), sodium metabisulfite (Na2S2O5) or hydrogen peroxide (H2O2) in 2M H2SO4, the Mn extraction efficiency for Mn was increased from 21.9% (with no reducing agent) up to 48.4%, 82.8% and 98.9%, respectively. The upscale leaching study was subsequently performed in a 100-L pilot scale reactor demonstrated the Zn and Mn extraction efficiencies of 71% and 65%, respectively. Using the leaching solutions from the upscale hydrometallurgical route, Zn-film fabrication via electrodeposition process, and the MnO2 and MnO2/C synthesis via hydrothermal techniques were performed. Additionally, the one-step synthesis of MnO2/C via one-step hydrothermal method with no acid leaching was also explored in this study. The recycled Zn, MnO2, MnO2/C and C residual were subsequently used as the anode and cathode main components in the CR2032 and pouch-cell rechargeable Zn-ion batteries. The recycled MnO2 and MnO2/C provided similar performance as the commercial products, which indicating the recycled MnO2, MnO2/C could be effectively utilized in the Zn-ion battery, while the utilization of recycled Zn-film provided slightly lower performance compared to that of the commercial Zn foil.

Nickel-Based Metal-Organic Framework Materials with Mixed Ferrocene-Based Ligands As Anodic Catalysts for Water Electrolysis and Urea Electrolysis

Water electrolysis is a highly promising technology for hydrogen production, generating green hydrogen with no greenhouse gas emissions. The water electrolysis reaction involves two half-reactions: hydrogen evolution and oxygen evolution. While oxygen evolution in water electrolysis involves a four-electron transfer requiring higher overpotential and thus leading to energy consumption. Urea electrolysis offers lower theoretical energy consumption than water electrolysis, making them a key technology in future electrolytic hydrogen production processes. Conventional anodic catalysts, such as Ir and Ru, exhibit good performance in oxygen evolution, but being precious metals, they face limitations due to high cost and limited abundance. Its is crucial to find an active, durable and cost-effective anode catalyst for realistic application.Metal-organic framework (MOF) materials, due to their high porosity, large surface area, and unique structural features, have emerged as promising materials for water electrolysis. However, their relatively poor stability is a drawback that needs to be overcome. In herein, we design the mixed ligand strategy for synthesizing the MOF materials. Ferrocene-based ligands, ferrocenedicarboxylic acid (Fd), combing with terephthalic acid (H2BDC) as the mixed ligands for this study. The MOF catalysts, namely Ni-BDC and Ni-BDC-Fd, was synthesized using a simple one-step hydrothermal method with ferrocenedicarboxylic acid and terephthalic acid.Raman spectra revealed the presence of Fe-O, originating from the iron in Fd, demonstrating a structural transformation during the hydrothermal process. XRD analysis also confirmed the existence of FeO. The SEM images showed nanosheets and nanoneedles morphologies for Ni-BDC, while a dense nanofiber structure for Ni-BDC-Fd demonstrating the effect of 2nd ligand on the MOF structure.Electrochemical tests were conducted in 1 M KOH electrolyte and 1 M KOH + 0.5 M urea electrolyte, including oxygen evolution reaction (OER), urea oxidation reaction (UOR). The overall reaction comprising the same catalysts for the anode and the cathode side is performed to examine the real electrolysis performance.Results showed that the addition of Fd enhanced OER and UOR activity in alkaline and urea electrolytes. Ni-BDC-Fd achieved 1.483 V vs. RHE and 1.386 V vs. RHE at 65 mA/cm-2 driving potential for OER and UOR, respectively, requiring a smaller potential than Ni-BDC to achieve the same current density. To verify that the performance improvement was not solely due to iron, NiFe-BDC was synthesized by adding iron nitrate, showing inferior UOR performance compared to Ni-BDC-Fd but superior OER performance to NiFe-BDC. This indicated that the performance improvement resulted from structural changes rather than just the presence of iron atoms. Ni-BDC-Fd exhibited the lowest Tafel slope in OER, indicating a faster reaction rate due to the increased active surface area during OER. After continuous catalysis for 80 hours in the alkaline water electrolysis cell and urea electrolysis cell, a significant improvement in the loss of potential was observed.These results suggest that the addition of ferrocene dicarboxylic acid altered the structure of Ni-BDC, maintaining an appropriate interlayer distance. This not only enhanced its catalytic performance but also improved its catalytic stability, demonstrating a promising strategy for preparing metal-organic framework materials for electrocatalysis applications. Figure 1

Nitrogen-Tungsten Oxide Nanostructures on Nickel Foam as High Efficient Electrocatalysts for Benzyl Alcohol Oxidation.

Electrocatalytic alcohol oxidation (EAO) is an attractive alternative to the sluggish oxygen evolution reaction in electrochemical hydrogen evolution cells. However, the development of high-performance bifunctional electrocatalysts is a major challenge. Herein, we developed a nitrogen-doped bimetallic oxide electrocatalyst (WO-N/NF) by a one-step hydrothermal method for the selective electrooxidation of benzyl alcohol to benzoic acid in alkaline electrolytes. The WO-N/NF electrode features block-shaped particles on a rough, inhomogeneous surface with cracks and lumpy nodules, increasing active sites and enhancing electrolyte diffusion. The electrode demonstrates exceptional activity, stability, and selectivity, achieving efficient benzoic acid production while reducing the electrolysis voltage. A low onset potential of 1.38 V (vs. RHE) is achieved to reach a current density of 100 mA cm-2 in 1.0 M KOH electrolyte with only 0.2 mmol of metal precursors, which is 396 mV lower than that of water oxidation. The analysis reveals a yield, conversion, and selectivity of 98.41%, 99.66%, and 99.74%, respectively, with a Faradaic efficiency of 98.77%. This work provides insight into the rational design of a highly active and selective catalyst for electrocatalytic alcohol oxidation.

Adsorption characteristics and mechanisms of bisphenol A on novel nitrogen-modified biochar derived from waste masks and biomass.

Resource utilization of waste masks has become an urgent scientific issue. In this work, with sustainably, waste masks and biomass were co-pyrolysis with oxygen limitation to prepare mask-based biochar (MB). Then, urea was introduced to prepare novel nitrogen modified mask-based biochar (NMB) via a one-step hydrothermal synthesis method. The adsorption characteristics of NMB on the emerging environmental pollutant, bisphenol A (BPA), were evaluated via batch adsorption tests. Moreover, the physicochemical properties of the materials were characterized with various advanced techniques. Also, the roles of waste masks and nitrogen modification were explored. The adsorption mechanisms of NMB on BPA were revealed as well as the performance differences between different adsorbents. The results showed that waste masks participated in thermochemical reactions, shaped the microsphere structure of biochar, and increased the types of surface functional groups. The nitrogen modification enriched the surface elemental composition and activated the specific surface area via the mesopore. These would enhance the adsorption performance. The maximum adsorption of BPA by NMB was 62.63mg·g-1, which was approximately 2.35-5.58 times higher than that of the control materials. Temkin model and pseudo-second-order model optimally simulate the isothermal and kinetic adsorption, respectively. The adsorption mechanisms are jointly by physical and chemical adsorption, which mainly includes π-π interaction, hydrogen bonding, intraparticle diffusion, surface adsorption, and ion exchange. After discussion and evaluation, NMB has lower preparation process cost (7.21 USD·kg-1) and safety, with potential for environmental applications. This study aims to expand new ideas for the comprehensive utilization of waste masks and the preparation of eco-friendly materials. Moreover, it provides a theoretical basis for the removal of BPA.

Boosting catalytic performance with bismuth for extended lifespan of light-assisted lithium-oxygen batteries

Photo-assisted Li-O2 batteries have gained significant attention due to their low overpotential. However, the rapid recombination of photogenerated carriers remains a fundamental challenge. Herein, we utilized a one-step hydrothermal method to produce bismuth nanoparticles and loaded bismuth/titanium dioxide/carbon nanotubes onto nickel foam (Bi/TiO2/CNTs/NF) by ultrasonic loading. Bismuth nanoparticles accelerate the transfer of photogenerated electrons and prolong the recombination of photogenerated carriers. As a result, photogenerated carriers act quickly and effectively at the three-phase reaction and interface. Carbon nanotubes (CNTs) and nickel foam (NF) increase the micropores and mesopores of the electrode for oxygen transport and lithium-oxygen storage. Increases the active sites of the electrodes while providing more storage space for the generated lithium peroxide. Accordingly, the photo-assisted Li-O2 battery with Bi/TiO2/CNTs/NF photocathode exhibits excellent multiplicity performance and good reversibility. The charging potential of Bi/TiO2/CNTs/NF was 0.22 V lower than TiO2/CNTs/NF and exhibited excellent cycle stability under illumination (Battery energy efficiency drops by only 6 % after 500 cycles)(Table S1, Supporting Information). This study provides a reference for developing and applying photocatalysts in photo-assisted Li-O2 batteries.

Carbon dots for efficient detection of water content in organic solvents

The trace amount of water in organic solvents can affect the progress of chemical reactions, which will adversely affect chemical production in many industries, resulting in a doubling of costs. In this work, carbon dots (CDs) with abundant polar groups were synthesized by a simple one-step hydrothermal method. The prepared CDs showed superior dispersibility and fluorescence performance compared to the CDs that have been reported for the detection of water content in organic solvents. It can realize the fluorescence detection of trace water in several water-soluble organic solvents such as N,N-dimethylformamide, ethanol and methanol with wide linear range (0 %–100 %) and high sensitivity. This will provide a powerful tool for the rapid detection of water content in organic solvents in chemical production.

Enhanced electrochemical performance of nickel cobalt sulfide microspheres for high energy symmetric supercapacitors

Herein, Nickel cobalt sulfide (NCS) microspheres are successfully synthesized by an easy one-step hydrothermal method at different reaction conditions. The as-synthesized samples are used as electrode material to demonstrate their practical application for supercapacitors (SCs). Various techniques including X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Scanning electron microscopy (SEM), Energydispersive X-ray (EDX) spectroscopy are used for structural and morphological characterization of the synthesized materials which confirmed the successful formation of NCS. The electrochemical performance of prepared samples is tested using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). The optimized NCSW-200 sample delivered a remarkable specific capacitance of 369 F g−1 at 0.5 A g−1. The energy and power density exhibited by NCSW-200 sample are as high as 32.8 Wh kg−1 and 266.6 W kg−1, respectively. After 2000 consecutive charge/discharge cycles, capacitance retention of 67% is achieved, depicting better cyclic stability. To illustrate the practical feasibility of the prepared symmetric cells of the optimized sample NCSW-200, a lab scale setup of three SC cells connected in series is fabricated and tested using a red light emitting diode (LED). The SC setup is able to illuminate a red LED for 2.5 minutes. The electrochemical performance demonstrated by NCS microspheres suggests its viable application as supercapacitor electrodes.

One-step preparation of Z-scheme g-C3N4 nanorods/TiO2 microsphere with improved photodegradation of antibiotic residue

Graphitic carbon nitride nanorods/titanium dioxide microspheres (g-C3N4 NRs/TiO2 MSs) Z-scheme heterojunctions were simply prepared by a one-step hydrothermal method, which showed improved visible-light-induced photocatalytic activity for the degradation of tetracycline hydrochloride (TC-HCl). The photodegradation activity of g-C3N4 NRs/TiO2 MSs is 6.6 and 1.9 times better than that of pristine g-C3N4 and TiO2, which is assigned to the unique morphology and formed heterojunction. Hydroxyl radical (⋅OH) and superoxide radical (⋅O2−) were the main species for TC-HCl photodegradation according to capture experiments, and a possible mechanism is proposed. This study provides an effective reference for the preparation of binary heterostructures with excellent photocatalytic activity from a simplified process.

Fabrication of Ag nanowires and Ag-graphite nanocomposite conductive adhesives by one-step hydrothermal method

Fabrication of Ag nanowires and Ag-graphite nanocomposite conductive adhesives by one-step hydrothermal method

Luminescence performance and antioxidant properties of selenium carbon dots prepared from selenium-hyperaccumulating plants.

Heteroatom doping has become an important method to enhance the performance of traditional carbon dots in modern times. Selenium (Se) is a nonmetallic trace element with excellent redox properties and is therefore essential for health. Previous studies have mainly used pure chemicals as selenium sources to prepare selenium-doped carbon dots (Se-CDs), but the precursor pure chemicals have the disadvantages of being expensive, difficult to obtain, toxic, and having low fluorescence yields of the synthesised Se-CDs. Fortunately, our team achieved successful synthesis of selenium carbon dots, exhibiting excellent luminescence and biocompatibility through a one-step hydrothermal method using selenium-enriched natural plant Cardamine, as an alternative to selenium chemicals. This approach aims to address the limitations and high costs associated with Se-CDs precursors. Electron spin resonance spectroscopy (ESR) and cellular antioxidant tests have confirmed the protective ability of Se-CDs against oxidative damage induced by excessive reactive oxygen species (ROS). A new concept and method for synthesizing selenium carbon dots on the basis of biomass, a rationale for the antioxidant effects on human health, and a wide range of development and application possibilities were offered in this work.

A sensitive enzyme-free electrochemical sensor based on ZnWO4@co-MNPC@MIP for specific recognition and determination of chloramphenicol in milk sample

We have carefully built a new chloramphenicol (CAP) electrochemical sensor, which takes the zinc tungstate @ cobalt magnetic nanoporous carbon @ molecularly imprinted polymer (ZnWO4@Co-MNPC@MIP) as the core. First, we successfully prepared Co-MNPC nanomaterials using an efficient one-step hydrothermal method and a direct carbonization method. Next, we recombined ZnWO4 with Co-MNPC and synthesized the completely new ZnWO4@Co-MNPC complex by using the hydrothermal method. To further improve its performance, we combined ZnWO4@Co-MNPC with a molecular imprinted polymer and coated a molecular imprinted (MIP) shell on the surface of ZnWO4@Co-MNPC by precipitation polymerization. This shell not only gives the sensor a new performance but also gives it a stronger peak current, resulting in a more accurate detection of CAP. Under optimal conditions, the ZnWO4@Co-MNPC@MIP (MMIP) electrode has a stronger CAP detection peak current than the one-component electrode, with a fairly wide linear range: 0.007–200 μM and 200–1400 μM. Even more surprisingly, the detection limit is as low as 0.0027 μM, which allows the sensor to maintain excellent selectivity and stability in the face of various interferences, making it an excellent electrochemically modified electrode. Compared to magnetic non-molecular imprint sensors (MNIPs), MMIP sensors have higher detection efficiency. After practical application, we found that the ZnWO4@Co-MNPC@MIP modified electrode was satisfactory in milk samples.