- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Phytosynthesis of Au and Au/ZrO <sub/>2</sub> bi-Phasic System Nanoparticles with Evaluation of Their Colloidal Stability
摘要： Due to its easy availability, preparation, handling and non-toxic nature, Equisetum arvense horsetail extract was chosen as a reducing, stabilizing and functionalizing agent for Au and bi-phasic Au/ZrO2 nanoparticle phytosynthesis–inorganic nanoparticle synthesis mediated by plant extract. We studied Au and bi-phasic Au/ZrO2 nanoparticles in colloids by various physical-chemical and analytical methods over 5 weeks. Dynamic Light Scattering and Scanning Transmission Electron Microscopy compared core and hydrodynamic diameters of nanoparticles. (cid:2)-potential measurement indirectly determined nanoparticles stability in liquid medium. Ultraviolet–Visible Spectroscopy characterized basic absorbance maxima for both Au and the bi-phasic Au/ZrO2 system. Finally, total metal concentration was determined using Inductively Coupled Plasma Mass Spectrometry. (cid:2)-potential measurements proved satisfactory stability of both Au (?13(cid:3)4 to ?17 mV) and Au/ZrO2 nanoparticles (?14(cid:3)1 to ?17(cid:3)5 mV) over the experimental period. Scanning Transmission Electron Microscopy with Selected Area Diffraction analysis con?rmed nanoparticles crystalline nature, and we determined 24 nm and 40 nm core nanogold diameters in Au and Au/ZrO2 nanoparticle colloids. Dynamic light scattering analysis con?rmed the dichotomy between particle sizes in liquid medium in the hundreds of nanometers measured, and long-term measurements con?rmed reasonable colloid stability—a paramount parameter for potential nanoparticles applications; especially in heterogeneous catalysis.
关键词： Stability,Au/ZrO2 Nanoparticles,Phytosynthesis,Colloid,Au Nanoparticles
更新于2025-09-04 15:30:14
-
Pd/TiO2 @ Carbon Microspheres Derived from Chitin for Highly Efficient Photocatalytic Degradation of Volatile Organic Compounds
摘要： Facing the serious air pollution caused by the volatile organic compounds (VOCs), the highly efficient degradation and removal of VOCs have attracted great attentions. To develop efficient novel photocatalysts, Pd/TiO2 @ carbon nanofibrous microspheres were constructed by carbonizing the TiO2/chitin microspheres, followed by immobilizing Pd nanoparticles on the TiO2/carbon microspheres via a green pathway. The composite microspheres were composed of carbon nanofibers, on which TiO2 nanoparticles and ultra-small Pd nanoparticles with mean size of 1 nm were well immobilized and distributed, supported by transmission electron microscope and elemental mappings results. The Pd/TiO2 @ carbon microspheres were used for the gas phase photodegradation of VOCs. The results demonstrated that the conversion of toluene and benzene to CO2 and H2O reached 96.4% and 91.7%, respectively, which were higher than the reported values in the literatures. The combination of TiO2 and Pd nanoparticles played an important role on the enhancement of the catalytic activity. Moreover, the Pd/TiO2 @ carbon microspheres could be recycled and reused. This work provided a new strategy to eliminate VOCs, which was beneficial to a sustainable world.
关键词： catalyst TiO2 nanoparticles,Chitin microsphere,Pd nanoparticles,degradation of volatile organic compounds,carbon nanofibers
更新于2025-09-04 15:30:14
-
Nanoparticles at Biomimetic Interfaces: A Combined Experimental and Simulation Study on Charged Gold Nanoparticles/Lipid Bilayers Interfaces
摘要： The poor understanding of the interaction of nanomaterials with biologically relevant interfaces is recognized as one of the major issues currently limiting the development of nanomedicine. The central purpose of this study is to compare experimental (Confocal Microscopy, Fluorescence Correlation Spectroscopy, X-ray Reflectivity) and computational (Molecular Dynamics simulations) results to thoroughly describe the interaction of cationic gold nanoparticles (AuNP) with mixed zwitterionic/anionic lipid membranes. The adhesion of AuNPs to the lipid membrane is investigated on different length scales from a structural and dynamical point of view; with this approach, a series of complex phenomena, spanning from lipid extraction, localized membrane disruption, lateral phase separation and slaved diffusion, are characterized and interpreted from a molecular level to macroscopic observations.
关键词： Nanoparticles,Gold Nanoparticles,Molecular Dynamics,X-ray Reflectivity,Fluorescence Correlation Spectroscopy,Lipid Bilayers,Biomimetic Interfaces,Confocal Microscopy
更新于2025-09-04 15:30:14
-
Iron Oxide Nanoparticles as Potential Scaffold for Photocatalytic and Sensing Applications
摘要： Herein, we report photocatalytic and ?uorescence sensing applications of iron oxide (α-Fe2O3) nanoparticles synthesized by facile low-temperature simple solution process. The synthesized nanoparticles were characterized by several techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM) attached with energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), UV-visible spectroscopy and ?uorescence spectroscopy. The detailed analysis revealed that the synthesized nanoparticles were well-crystalline, grown in very high density and possessing rhombohedral α-Fe2O3 crystal structure. The prepared nanoparticles were used as ef?cient scaffold for photocatalytic and sensing applications. The detailed photocatalysis results revealed that in presence of an appropriate amount of α-Fe2O3 nanoparticles as photocatalyst, a signi?cant dye degradation of methyl orange (MO) was observed in 140 min. In addition, the fabricated ?orescence sensor based on α-Fe2O3 nanoparticles exhibited a low detection limit of ～3.33 μM/L towards picric acid. The observed results clearly con?rmed that the synthesized α-Fe2O3 nanoparticles are potential scaffold for photocatalysis and sensing applications.
关键词： Picric Acid,Photocatalysis,Methyl Orange,α-Fe2O3 Nanoparticles
更新于2025-09-04 15:30:14
-
Microcystis aeruginosa Synergistically Facilitate the Photocatalytic Degradation of Tetracycline Hydrochloride and Cr(VI) on PAN/TiO2/Ag Nanofiber Mats
摘要： Cyanobacterial blooms can cause serious damage to aquatic ecosystems. However, we have demonstrated that typical algae-blooming species Microcystis aeruginosa (M. aeruginosa) combined with photocatalysts could synergistically facilitate the photodecontamination of tetracycline hydrochloride (TC) and Cr(VI). In this study, for the first time, harmful algae were successfully converted into photoreactive bionano hybrid materials by immobilizing M. aeruginosa cells onto polyacrylonitrile (PAN)-TiO2/Ag hybrid nanofibers, and their photocatalytic activity was evaluated. The addition of M. aeruginosa significantly improved the photodecontamination, and the reaction rate constant (k) values of TC and Cr(VI) degradation by M. aeruginosa-PAN/TiO2/Ag nanofiber mats were 2.4 and 1.5-fold higher than that of bare PAN/TiO2/Ag nanofiber. Photoreaction caused damage to algae cells, but no microcystin was found that had been photodegraded simultaneously. The effects of various active species were also investigated, and the photodegradation mechanism was proposed. Recycling tests revealed that this flexible M. aeruginosa-PAN/TiO2/Ag hybrid mat had potential application in the removal of mixed organic and inorganic pollutants with high efficiency and without secondary pollutants. Thus, harmful algae blooms could serve as an efficient materials to remove toxic pollutants in a sustainable way under visible light irradiation.
关键词： Ag nanoparticles,PAN nanofiber,Cr(VI),tetracycline,TiO2 photocatalytic,Microcystis aeruginosa
更新于2025-09-04 15:30:14
-
Amorphous Quantum Nanomaterials
摘要： In quantum materials, macroscopic behavior is governed in nontrivial ways by quantum phenomena. This is usually achieved by exquisite control over atomic positions in crystalline solids. Here, it is demonstrated that the use of disordered glassy materials provides unique opportunities to tailor quantum material properties. By borrowing ideas from single-molecule spectroscopy, single delocalized π-electron dye systems are isolated in relatively rigid ultra-small (<10 nm diameter) amorphous silica nanoparticles. It is demonstrated that chemically tuning the local amorphous silica environment around the dye over a range of compositions enables exquisite control over dye quantum behavior, leading to efficient probes for photodynamic therapy (PDT) and stochastic optical reconstruction microscopy (STORM). The results suggest that efficient fine-tuning of light-induced quantum behavior mediated via effects like spin-orbit coupling can be effectively achieved by systematically varying averaged local environments in glassy amorphous materials as opposed to tailoring well-defined neighboring atomic lattice positions in crystalline solids. The resulting nanoprobes exhibit features proven to enable clinical translation.
关键词： photodynamic therapy (PDT),optical super-resolution microscopy,organic dyes,amorphous silica nanoparticles
更新于2025-09-04 15:30:14
-
Physical Properties of Pure and Nano Ag Doped Liquid Crystalline Compounds Containing 1,3,4-Oxadizole Unit
摘要： Dielectric properties and other physical properties such as electrical conductivity (AC) and relaxation time or activation energy have been studied for two systems pure LC [V]6,6, [V]7,6, [V]8,6, [V]6,7, [V]7,7 and [V]8,7 and their doped with silver nanoparticles. The results show the increasing in real dielectric permittivity ? with increasing length terminal chain. So the real dielectric permittivity increasing with raising temperature. To compare between the values of (400) Hz and (4000) Hz we observe these values at the low frequency are larger than that in high frequency. Generally, one can see that the doping of Ag nano particles effectively reduced the permittivity of the LC materials with its large electric dipole moment. The electrical conductivity σ value for pure LC samples in general increases with increasing temperature. So we observed increasing of electrical conductivity values at high frequency. The time scale is discussed in terms of the Arrhenius plot. Generally, with increasing the temperature the time period that spends by molecules at the transition state will increase. The activation energy Ea values show the increase in the activation energy to the doped systems.
关键词： Dielectric permittivity,Doped liquid crystals,Liquid crystals,Relaxation time,Electrical conductivity,Activation energy,Silver nanoparticles
更新于2025-09-04 15:30:14
-
Fluorescent Chemosensor for Quantitation of Multiple Atmospheric Gases
摘要： Recently, the sensing and monitoring of gases from ambient as well as industrial sources has gained a great importance in order to ensure occupational hygiene, public health, and societal welfare. The development of new technologies for visualizing and detecting gases at trace levels is imperative for various applications. There exist several established traditional methods to detect different gases. In this article, we review the latest trends in the area of fluorescence sensing of gas molecules, which is a high sensitivity technique with minimum or negligible interferences. The gas sensors fabricated with the use of fluorescent nanoparticles as detecting elements possess special feature, like high surface-to-volume ratios, ultra sensitivity, enhanced selectivity, cost effectiveness, and fast response. The inherent properties of the related systems, e.g. a large fluorescence lifetime, nanoscale particle size and a tunable zeta potential, make it possible to devise fluorescent sensors with an attractive pathway of fluorescence ‘off–on’. Several fluorimetric methods are known to detect specific gases from the atmospheric gaseous samples with satisfactory detection results. Modern fluorescent gas sensors are did not cause interference from the co-pollutants thus making the fluorimetric sensing process to be quantitative as well as specific.
关键词： Atmospheric environmental sample,Fluorescent gas sensor,Job’s plot,Fluorescent organic nanoparticles,Analytical method,Fluorescence lifetime
更新于2025-09-04 15:30:14
-
Etching reaction-based photoelectrochemical immunoassay of aflatoxin B1 in foodstuff using cobalt oxyhydroxide nanosheets-coating cadmium sulfide nanoparticles as the signal tags
摘要： A new split-type photoelectrochemical (PEC) immunosensing platform was designed for sensitive detection of aflatoxin B1 (AFB1) in foodstuffs, coupling with enzymatic hydrolysate-triggered etching reaction of cobalt oxyhydroxide (CoOOH) on cadmium sulfide (CdS) nanoparticles-functionalized interface. Initially, the photosensitive electrode was prepared by coating CoOOH nanosheets on the surface of CdS nanoparticles to quench the photocurrent. Thereafter, a competitive-type enzyme immunoreaction was carried out on monoclonal anti-AFB1 antibody-conjugated magnetic bead by using alkaline phosphatase (ALP)-labeled bovine serum albumin-AFB1 (AFB1-BSA) conjugate as the competitor. With the formation of immunocomplex, the carried ALP hydrolyzed ascorbic acid 2-phosphate (AAP) into ascorbic acid (AA) and phosphate. The former ascorbic acid produced etched or dissolved CoOOH nanosheets into Co2+ ions, thus resulting in the exposure of CdS nanoparticles on the surface to enhance the photocurrent of the modified electrode. Under optimum conditions, the photocurrent decreased linearly with the increasing AFB1 concentration in the dynamic range of 0.01 – 10 ng mL-1, and the limit of detection was 2.6 pg mL-1. The precision of this method (expressed as RSD) was ± 8.6%. In addition, the accuracy was monitored by analyzing spiked food samples, and gave the well-matched results with the referenced ELISA method.
关键词： cobalt oxyhydroxide nanosheets,cadmium sulfide nanoparticles,aflatoxin B1,photoelectrochemical immunoassay,etching reaction
更新于2025-09-04 15:30:14
-
Enhanced Electrocatalysis via Boosted Separation of Hot Charge Carriers of Plasmonic Gold Nanoparticles Deposited on Reduced Graphene Oxide
摘要： The plasmon enhancement on electrocatalysis was investigated on pure Au nanoparticles (AuNPs) and AuNPs-reduced graphene oxide (AuNPs/rGO) hybrid. Upon Localized surface plasmon resonance (LSPR) excitation, hot charge carriers (hot electrons and holes) generate on AuNPs. In the experiments, hot holes are scavenged by glucose, and hot electrons could be efficiently transferred to the external electric circuit under a potential bias, resulting in an observable current enhancement. Then the hot electrons transfer efficiency can be quantitatively compared by the increased current response. It was found that the current density increases more obviously on AuNPs/rGO hybrid compared to pure AuNPs upon light irradiation. Due to the excellent electron mobility of rGO and perfect electron affinity capacity, the hot electrons generated on AuNPs will be efficiently transferred to the closely contacted rGO, then flow into the external circuit generating current. The present study highlights the role of rGO in improving the separation of hot charge carriers to promote the photocatalysis reactions.
关键词： Au nanoparticles (AuNPs),Hot charge carriers,Localized surface plasmon resonance (LSPR),Graphene,Electrochemical method
更新于2025-09-04 15:30:14