- 标题
- 摘要
- 关键词
- 实验方案
- 产品
过滤筛选
- 2019
- Au nanoparticles in water
- Fourier-Zhukovsky thermal model
- Nanomaterials and Technology
- National Institute for Laser, Plasma and Radiation Physics
-
Peptide Conjugated CuS Nanocomposites for NIR Triggered Ablation of Pseudomonas aeruginosa Biofilm
摘要： The Gram-negative bacteria Pseudomonas aeruginosa is one famous bacterial strain owing to its ability to effectively form biofilms, which is a front-line mechanism of bacterial tolerance. Herein, the near-infrared-induced nanocomposites were one-step prepared by modifying copper sulfide nanoparticle with peptide to effectively eradicate Pseudomonas aeruginosa biofilm through electrostatic interaction, photodynamic effect and photothermal effect. These nanocomposites could rapidly adhere to the surface of bacteria, and irreversible damage the bacterial membrane under near-infrared laser irradiation. Furthermore, the nanocomposites could selectively eliminate bacteria over mammalian cell without distinct toxicity to NIH 3T3 cells. The nanocomposites will exert a far-reaching impact on the future design of biocompatible near-infrared-induced antibacterial agents, exhibiting its potential applications in Gram-negative bacteria and biofilm infections.
关键词： copper sulfide nanoparticles,near-infrared laser,Gram-negative bacterial biofilm,photothermal and photodynamic effect
更新于2025-11-14 17:03:37
-
α-Fe <sub/>2</sub> O <sub/>3</sub> Polyhedral Nanoparticles Enclosed by Different Crystal Facets: Tunable Synthesis, Formation Mechanism Analysis, and Facets-dependent <i>n</i> -Butanol Sensing Properties
摘要： Three kinds of polyhedral α-Fe2O3 nanoparticles enclosed by different facets including oblique parallel hexahedrons (op-hexahedral NPs), cracked oblique parallel hexahedrons (cop-hexahedral NPs), and octadecahedral nanoparticles (octadecahedral NPs), were successfully prepared by simply changing only one reaction parameter in the hydrothermal process. The structural and morphological of the products were systematically studied using various characterizations including X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), revealing that the three kinds of α-Fe2O3 nanoparticles were enclosed by {104}, {110}/{104}, and {102}/{012}/{104} crystal planes, respectively. The exposed facets and shape of the nanocrystals were found to be affected by the adding amount of ethylene glycol in the solvent. The gas-sensing properties and mechanism of the α-Fe2O3 samples were studied and analyzed, which indicated that the sensitivity of the three samples followed the order of octadecahedral NPs (cid:2) cop-hexahedral NPs (cid:2) op-hexahedral NPs due to the combined effects of specific surface area and oxygen defects in the nanocrystals.
关键词： Polyhedron,n-Butanol,Hydrothermal synthesis,α-Fe2O3 nanoparticles,Gas-sensing
更新于2025-11-14 17:03:37
-
Novel PtPd alloy nanoparticle-decorated g-C3N4 nanosheets with enhanced photocatalytic activity for H2 evolution under visible light irradiation
摘要： PtPd bimetallic alloy nanoparticle (NP)-modified graphitic carbon nitride (g-C3N4) nanosheet photocatalysts were synthesized via chemical deposition precipitation. Characterization of the photocatalytic H2 evolution of the g-C3N4 nanosheets shows that it was significantly enhanced when PtPd alloy NPs were introduced as a co-catalyst. The 0.2 wt% PtPd/g-C3N4 composite photocatalyst gave a maximum H2 production rate of 1600.8 μmol g–1 h–1. Furthermore, when K2HPO4 was added to the reaction system, the H2 production rate increased to 2885.0 μmol g–1 h–1. The PtPd/g-C3N4 photocatalyst showed satisfactory photocatalytic stability and was able to maintain most of its photocatalytic activity after four experimental photocatalytic cycles. In addition, a possible mechanism for the enhanced photocatalytic activity was proposed and verified by various photoelectric techniques. These results demonstrate that the synergistic effect between PtPd and g-C3N4 helps to greatly improve the photocatalytic activity of the composite photocatalyst.
关键词： H2 evolution,PtPd alloy nanoparticles,Photocatalysis,g-C3N4 nanosheets
更新于2025-11-14 17:03:37
-
Photocatalytic CO2 reduction on porous TiO2 synergistically promoted by atomic layer deposited MgO overcoating and photodeposited silver nanoparticles
摘要： In this work, a porous TiO2 photocatalyst derived from metal-organic framework MIL-125 was synthesized and tested for photocatalytic CO2 reduction with water. To improve the photocatalytic performance, innovative materials modifications were employed by decorating TiO2 with atomic layer deposited (ALD) MgO overcoating and photodeposited silver (Ag) nanoparticles at different orders: MgO deposition followed by Ag (i.e. Ag/MgO/TiO2), or Ag deposition followed by MgO (i.e. MgO/Ag/TiO2). The addition of Ag promoted transfer of photoinduced electrons, while the coating of an ultrathin MgO layer inhibited surface charge recombination and enhanced CO2 adsorption. The combination of MgO and Ag resulted in synergistic promotion on CO2 photoreduction greater than the sum of individual promotional effects. The Ag/MgO/TiO2 catalyst with 7 ALD-layers of MgO and 5% Ag was 14 times more active than the pristine TiO2 in terms of CO and CH4 production. In addition, the sequence of MgO/Ag decoration influenced the catalytic activity. The Ag/MgO/TiO2 catalysts were in general more active than the MgO/Ag/TiO2 counterparts, likely due to the different electron mobility and Ag nanoparticle distribution on the surface. This work for the first time reports the novel materials structure of ALD coated MgO and photodeposited Ag nanoparticles on TiO2, and it reveals the importance of optimizing materials morphology and structure to promote the catalytic activity.
关键词： CO2 photoreduction,magnesium oxide,silver nanoparticles,atomic layer deposition,porous TiO2
更新于2025-11-14 17:03:37
-
Synthesis of Silver Nanoparticles Loaded onto Polymer-Inorganic Composite Materials and Their Regulated Catalytic Activity
摘要： We present a novel approach for the preparation of polymer-TiO2 composite microgels. These microgels were prepared by the in situ hydrolysis and condensation of titanium tetrabutoxide (TBOT) in a mixed ethanol/acetonitrile solvent system, using poly(styrene-co-N-isopropylacrylamide)/poly(N-isopropylacrylamide-co-methacrylic acid) (P(St-NIPAM/P(NIPAM-co-MAA)) as the core component. Silver nanoparticles (AgNPs) were controllably loaded onto the polymer-TiO2 composite microgels through the reduction of an ammoniacal silver solution in ethanol catalyzed by NaOH. The results showed that the P(St-NIPAM)/P(NIPAM-co-MAA)-TiO2 (polymer-TiO2) organic-inorganic composite microgels were less thermally sensitive than the polymer gels themselves, owing to rigid O–Ti–O chains introduced into the three-dimensional framework of the polymer microgels. The sizes of the AgNPs and their loading amount were controlled by adjusting the initial concentration of [Ag(NH3)2]+. The surface plasmon resonance (SPR) band of the P(St-NIPAM)/P(NIPAM-co-MAA)-TiO2/Ag (polymer-TiO2/Ag) composite microgels can be tuned by changing the temperature of the environment. The catalytic activities of the polymer-TiO2/Ag composite microgels were investigated in the NaBH4 reduction of 4-nitrophenol. It was demonstrated that the organic-inorganic network chains of the polymer microgels not only favor the mass transfer of the reactant but can also modulate the catalytic activities of the AgNPs by tuning the temperature.
关键词： silver nanoparticles,supported catalysts,polymer microgels,titania,reduction of 4-nitrophenol (4-NP)
更新于2025-11-14 17:03:37
-
Direct synthesis of ultrasmall and stable magnetite nanoparticles coated with one single carbon layer for sensitive surface-enhanced Raman scattering
摘要： Ultrasmall spherical magnetite nanoparticles (Fe3O4 NPs) coated with one single carbon layer (Fe3O4@1C NPs) were directly synthesized by a simple, fast one-step hydrothermal reaction at low temperature (200℃). The as-synthesized Fe3O4@1C NPs were easily separated and purified from the resultant mixture, without the need for any additional energy input and chemicals. The as-purified Fe3O4@1C NPs not only displayed typical superparamagnetic behavior but also exhibited quite good long-term stability after being exposed to the open air under the room conditions for more than 2 months. Importantly, the long-term stored Fe3O4@1C NPs exhibited a highly sensitive surface-enhanced Raman spectroscopy (SERS) response toward Rhodamine-b (RdB) molecules with low concentration. The multifunctional and recyclable Fe3O4@1C NPs presented a prospective application for the selective enrichment and sensitive SERS detection of chemical and biomolecular assays.
关键词： coated with one single carbon layer (Fe3O4@1C NPs),Dehydration reaction,Saturation magnetization,Long-term stability,Magnetite nanoparticles (Fe3O4 NPs)
更新于2025-11-14 17:03:37
-
Well‐Defined Cu <sub/>2</sub> O/Cu <sub/>3</sub> (BTC) <sub/>2</sub> Sponge Architecture as Efficient Phenolics Scavenger: Synchronous Etching and Reduction of MOFs in confined‐pH NH <sub/>3</sub> ?H <sub/>2</sub> O
摘要： Fabrication of low-dimensional nano-MOFs as well as nanoparticles/metal-organic frameworks (MOFs) hybrids has sparked new scientific interests but remains a challenging task. Taking Cu3(BTC)2 as a proof of concept, it is demonstrated thats NH3?H2O solution of a confined pH value can readily shape the bulk Cu3(BTC)2 into nanoscale Cu3(BTC)2, beyond the need to control the crystal growth kinetics of MOFs. Adjusting the pH of NH3?H2O within a much small range (10–11) allows fine tuning over the size and shape of nanoscale Cu3(BTC)2. Particularly at pH = 11, NH3?H2O exhibits weak reducibility that triggers a reduction of part of Cu3(BTC)2 into Cu2O, while shaping the other into Cu3(BTC)2 nanowires. Benefiting from the coincidence of reduction and etching effects, the newly generated Cu2O dots can in situ anchor onto adjacent Cu3(BTC)2 nanowires at highly dispersive state, forming a well-defined sponge-like architecture built of Cu2O dots and nano-Cu3(BTC)2. The CuOx derived from annealing of the Cu2O dots/nano-Cu3(BTC)2 hybrid preserves the sophisticated sponge architecture and high porosity, and exhibits promising applications in phenol scavenging, with efficiency outperforming its counterparts and many other Cu-based catalysts reported in literature. It is anticipated that the findings here pave the way for the rational design of intricate nano-MOFs in a more efficient way.
关键词： nanoparticles/MOF,etching and reduction,sponge architecture,synergistic effect,low-dimensional MOFs
更新于2025-11-14 17:03:37
-
Sensitive surface-enhanced Raman scattering detection of atrazine based on aggregation of silver nanoparticles modified carbon dots
摘要： The development of precise detection methods with simply operation for pesticides in various environmental samples is a particular challenge. Here a highly sensitive surface-enhanced Raman scattering (SERS) approach for the selective detection of trace atrazine was proposed with R6G as a Raman reporter, which was adsorbed on silver nanoparticles modified carbon dots. The latter were prepared by the reduction of Ag+ by carbon dots. In the presence of atrazine, the aggregation of the modified carbon dots due to the interaction between silver nanoparticles and atrazine led to great enhancement of the SERS signal of R6G. Under optimal assay conditions, the limit of quantification was estimated to be 10 nM, which matched with the standard for drinking water quality of China and WHO defined limit. A good linear response to atrazine was found in the concentration range of 10-1000 nM with the relative standard deviations between 1.8% and 5.6%. The determination of atrazine in real water samples was also carried out to confirm the practicability of the proposed method, which showed the recoveries from 95% to 117.5%. The target induced aggregation for enhancing the signal offered great potential for sensitive on-site detection of atrazine in environments.
关键词： Silver nanoparticles,Pesticides,SERS detection,Target induced aggregation,Atrazine,Carbon dots
更新于2025-11-14 17:03:37
-
Ultraviolet light assisted heterogeneous Fenton degradation of tetracycline based on polyhedral Fe3O4 nanoparticles with exposed high-energy {110} facets
摘要： Polyhedral Fe3O4 nanoparticles (NPs) with exposed high-energy {110} facets were synthesized by hydro-thermal method using ferrous sulfate and sodium thiosulfate as precursor at 140 °C. The as-synthesized catalysts were characterized via X-ray powder diffraction (XRD), electro impedance spectra (EIS), scanning electron microscope (SEM), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM) at room temperature. The well-defined Fe3O4 NPs with exposed high-energy {110} facets distributed a wide size, and the percentage of {110} facets was approximately 38.5% for single Fe3O4 NPs crystal. The synergistic effect of UV irradiation and the polyhedral Fe3O4 NPs improved the photodegradation efficiency of tetracycline (TC). The degradation efficiency of polyhedral Fe3O4 NPs catalyzing UV-Fenton system reached 96.7% after 60 min reaction, which was more substantial than polyhedral Fe3O4/H2O2 system (40%) and spherical Fe3O4 NPs catalyzing UV-Fenton system (28%) after 60 min reaction. The TOC degradation efficiency reached 56.5% for polyhedral Fe3O4 NPs catalyzing UV-Fenton after 120 min reaction, while UV/H2O2 system and spherical Fe3O4 NPs catalyzing UV-Fenton was 36.0% and 22.1% respectively after 120 min reaction. Moreover, polyhedral Fe3O4 NPs catalyzing UV-Fenton system exhibited an extremely wide pH range (from 3.0 to 9.0) for efficient degradation of TC. Simultaneously, the extraordinary high degradation efficiency was based on 10 mM H2O2 concentration, which had low requirement for H2O2. Further, the polyhedral Fe3O4 NPs could be reused for five consecutive cycles while still achieving at 91.7% of its original degradation efficiency and recycled under a magnetic field along with excellent chemical stability. Ultraviolet light assisted heterogeneous Fenton in the polyhedral Fe3O4 NPs system improved the ?OH and O2?- production efficiency and Fe(III)/Fe(II) redox cycle, which consequently achieved an excellent degradation efficiency.
关键词： heterogeneous UV-Fenton,Polyhedral Fe3O4 nanoparticles,high-energy {110} facets,tetracycline degradation
更新于2025-11-14 17:03:37
-
Facile Interface Self-Assembly of Gold Nanoparticles as Surface-Enhanced Raman Scattering Substrate for Monitoring the Reduction of p-Nitrophenol
摘要： A facile interface self-assembly method was proposed to fabricate the gold monolayer film without any specific molecular cross-linkers. The film was served as a surface-enhanced Raman scattering substrate, which exhibited high enhancement and reproducibility to the 1 × 10-9 M rhodamine 6G aqueous solution. Based on the substrate, the in situ and real-time monitoring for the reduction of p-nitrophenol to p-aminophenol was demonstrated successfully.
关键词： Interfaces,Surface-enhanced Raman scattering,Self-assembly,Nanoparticles
更新于2025-11-14 17:03:37