- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Enhanced photoresponse characteristics of ZnO polymer nanocomposite: effect of variation of surface density of nanocrystals
摘要： Zinc oxide (40–100 nm size) nanocrystals were successfully grown on the surface of an organic polymer (cellulose) by a low-cost solution casting method. Zinc precursor (zinc nitrate hexahydrate) concentration was varied from 25–75 mM, to synthesize several sets of ZnO-cellulose nanocomposite (ZCNC). The morphology and size of the nanocrystals were studied by a field emission scanning electron microscope and due to variation in the precursor concentration, a significant change in the surface density of the nanocrystals was observed. The maximum surface density was perceived at a precursor concentration of 50 mM. The Brunauer–Emmett–Teller (BET) surface areas of the ZCNCs were estimated by the nitrogen adsorption–desorption method, and a maximum surface area of 2.861 m2/g was observed. The structure, as well as composition of the nanocomposite, were studied by X-ray diffraction and energy dispersive X-rays analysis, respectively. The electrical properties of the composite were studied by current–voltage measurement while the photoresponse was recorded by time resolve photocurrent measurement. The photocurrent of the ZCNC sensor device increased from 6.783 × 10?8 to 4.91 × 10?6 A under UV illumination. The UV response (IUV/IDark) and sensitivity of the device were 72.38 and 7138, respectively. Also, the photocurrent rise time and decay time were 8 s and 9 s, respectively. The enhanced photoresponse with short response time observed for the ZnO-cellulose nanocomposite may lead to the fabrication of inexpensive ultraviolet sensors.
关键词： photoresponse,cellulose,nanocomposite,UV sensor,ZnO
更新于2025-09-19 17:13:59
-
Poly(3a??hexylthiophene)/Gold Nanorod Composites as Efficient Holea??Transporting Materials for Perovskite Solar Cells
摘要： Poly(3-hexylthiophene)/gold nanorod (P3HT/AuNR) composites were developed and introduced as hole-transporting materials (HTMs) to fabricate mixed-ion perovskite solar cells (PSCs). The power conversion efficiency (PCE) of the optimized devices based on the composite HTM reached up to 16.88%, which was an increase of 26% from that of a pristine P3HT-based device (13.40%). The enhanced performance can be attributed to the increased crystallinity of P3HT induced by the addition of AuNRs in the polymer matrix and the localized surface plasmon resonance (LSPR) effect of AuNRs, which lead to higher carrier mobility and increased light utilization efficiency. This work provides a comprehensive understanding of the effect of plasmonic Au nanorods in PSCs application and a useful method to further improve the performance of PSCs.
关键词： gold nanorod,hole-transporting materials,perovskite solar cells,nanocomposite,P3HT
更新于2025-09-19 17:13:59
-
Magnetic nanocomposite with fluorescence enhancement effect based on amino acid coated-Fe3O4 functionalized with quantum dots
摘要： Multifunctional nanoparticles with magnetic and fluorescent properties have high potential in different areas. A very attractive feature of these nanoparticles is that they can be controlled by an external magnetic field and monitored by fluorescence. For biological applications, the magnetic nanoparticles (MNPs) must be biocompatible and dispersible in water, which requires surface modification. This paper describes the synthesis of Fe3O4 MNPs modified with three amino acids (AA): L-Tryptophan (Trp), L-Phenylalanine (Phe) and L-Tyrosine (Tyr) by a co-precipitation method in a one-step reaction without the use of a spacer agent. The potential of AA as a robust anchor was assessed by binding mercaptopropionic acid (MPA)-coated CdTe quantum dots (QDs) to Fe3O4@AA nanoparticles, leading to a hybrid nanostructure with excellent fluorescent and magnetic properties. In particular, the Fe3O4@Trp@QDs nanocomposite showed a fluorescence enhancement effect due to F?rster resonance energy transfer (FRET) from Trp as energy donor to CdTe@QDs as acceptor. The nanomaterials were characterized by high-resolution transmission electron microscopy (TEM), X-Ray diffraction (XRD), zeta potential, thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), Fourier-transform infrared (FT-IR), UV-visible, and fluorescence spectroscopy. The nanocomposite also presents high stability and good dispersibility in water. This nanomaterial may be potentially used in different biomedical and environmental applications.
关键词： amino acid as anchor,fluorescent enhancement,energy transfer,stability and dispersibility in water,Magnetic and fluorescent nanocomposite,Fe3O4-amino acid-CdTe QD
更新于2025-09-19 17:13:59
-
One-pot synthesis of Mn3O4-coupled Ag2WO4 nanocomposite photocatalyst for enhanced photooxidative desulfurization of thiophene under visible light irradiation
摘要： The photooxidative desulfurization of thiophene (ThP) becomes a challenge in both industry and environmental remediation. Herein, we synthesize a visible-light-responsive Ag2WO4/Mn3O4 nanocomposite by a one-pot strategy. Depiction of the produced photocatalysts exposed the suppression of the surface structure and reduction of the bandgap energy by adding 15 wt% of Mn3O4 to Ag2WO4. The obtained nanocomposite shows a complete photooxidation of ThP within 1 h under visible light illumination at a dose of 1.2 g L?1. The significance of photocatalytic performance of Ag2WO4/Mn3O4 nanocomposite photocatalyst is referred to the enhancement of the visible light absorption and overthrow of the recombination of photogenerated charge carriers. The study opens the door for extensive use of nanocomposite photocatalysts as a novel functional material for the photooxidation of ThPs under visible light exposure.
关键词： Desulfurization,Photooxidation,Thiophene,Nanocomposite,Photocatalysts,Visible light
更新于2025-09-16 10:30:52
-
Core-shell nanocomposite of superparamagnetic Fe3O4 nanoparticles with poly(m-aminobenzenesulfonic acid) for polymer solar cells
摘要： Superparamagnetic Fe3O4 nanoparticles play a significant role in enhancing the performance and efficiency of polymer-based solar cells using nanocomposites. For the first time in this study, a novel superparamagnetic core-shell nanocomposite of poly(m-aminobenzenesulfonic acid) (PABS) and Fe3O4 was synthesized by in-situ polymerization of m-ABS as a monomer in the presence of FeCl3.6H2O as oxidant under solid-state conditions. The poly(m-aminobenzenesulfonic acid) (PABS)-Fe3O4 nanocomposite (NCPABS-Fe3O4) was characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) that revealed a core-shell morphology. Under simulated solar irradiation, the photovoltaic cell characteristics were measured. Based on our results, the polymer-hybrid solar cell was fabricated using FTO/TiO2/NCPABS-Fe3O4/Al and demonstrated a power conversion efficiency (PCE or η) 4.24% that was approximately 660% higher than those obtained from FTO/TiO2/(PABS)/Al. We have also proposed a new mechanism for the 660% enhanced efficiency. To the best of our knowledge, this is the highest enhancement reported in the literature. Our results showed that the polymer-hybrid solar cell was completely efficient with a high η in comparison with similar ones reported in literature, and also had less fabrication costs using green synthesis conditions with a simple structure and displayed resistance to oxidation with high stability.
关键词： conductive polymers,Fe3O4 nanoparticles,Solar cell,photovoltaics,core-shell nanocomposite
更新于2025-09-16 10:30:52
-
Photocatalytic degradation using TiO2-graphene nanocomposite under UV-LED illumination: Optimization using response surface methodology
摘要： Poor efficiency of TiO2 by visible light and the fast recombination rate of electron/hole pairs remain significant challenges in photocatalytic applications of TiO2 in water treatment. In this study, graphene was used to enhance TiO2 photocatalytic activity by reducing electron-hole pair recombination. Nanocomposites were formed by combining TiO2 nanoparticles (P25) with graphene oxide (GO) though simultaneous hydrothermal synthesis and GO reduction. Nanocomposite characterization confirmed that the GO was successfully reduced and P25 nanoparticles evenly dispersed in the graphene surface. The band gap of the nanocomposite was determined to be 2.74 eV, which is a promising shift to the visible spectrum in graphene-TiO2 photocatalysts. The photocatalytic performance of the TiO2/G nanocomposites was then evaluated by quantifying the formation of 2-hydroxyterephthalic acid (HTPA) (probe molecule) under UV-LED illumination. To further optimize the photocatalytic efficiency of the TiO2/G nanocomposites, the response surface methodology (RSM) with central composite design (CCD) was used. Out of the 6 variables including stirring time, stirring speed, the amount of TiO2, the amount of GO, hydrothermal reaction time, and ethanol/water ratio, it was determined that the last three are substantially affected the HTPA formation rate. The optimum conditions were found to be GO 0.48 wt%, ethanol/water 51.49 v/V%, and a reaction time 19 h. Predicted values for HTPA formation were found to be in good agreement with experimental values (R2 = 0.93 and adj-R2 = 0.87). The optimized nanocomposite showed 125% enhancement in photocatalytic efficiency over pure P25.
关键词： P25-graphene nanocomposite,DOE,Photocatalysis,Water treatment,RSM
更新于2025-09-16 10:30:52
-
Fabrication of Titanium Dioxide-reduced Graphene Oxide (TiO <sub/>2</sub> /rGO) nanocomposites as the Photoanode in Dye Sensitized Solar Cells
摘要： One of the photovoltaic cells generation promising for low-cost fabrication is dye-sensitized solar cell (DSSC). However, it has a drawback─low efficiency because of electron recombination occurrence and low transparency of photoanode. Graphene-based materials show the potential to overcome this problem. In this work, we have investigated the integration of reduced graphene oxide (rGO) into the titanium dioxide (TiO2) photoanode in DSSC. A simple Hummer’s method has been used to synthesize graphene oxide flakes. The nanocomposite of rGO/TiO2 has been formed by varying the percentage of rGO between 1% and 5%. The result shows that the percentage of rGO in nanocomposite affected device performance. The efficiency decreases along with the increase in rGO. The best result was obtained with 2 wt% addition of rGO into TiO2 photoanode that resulted in 0.9 % efficiency.
关键词： Dye-sensitized solar cell,titanium dioxide,nanocomposite,reduced graphene oxide,photoanode
更新于2025-09-16 10:30:52
-
Vertical Displacement of the Magnetooptical Hysteresis Loop in the Magnetoplasmonic Nanocomposite
摘要： The results of synthesis and investigation of magnetooptical (MO) properties of thin-film magnetoplasmonic nanocomposite, which is a layer of bismuth-substituted iron garnet Bi:YIG with plasmon nanoparticles Au, have been presented. The effect of vertical displacement of the MO hysteresis loop relative to the origin has been found in the study of MO-properties in the process of reversal magnetization of this magnetoplasmonic nanocomposite. It has been shown that the observed effect is most pronounced in the vicinity of the localized plasmon resonance in the system of metal nanoparticles that are part of the magnetoplasmonic composite.
关键词： magnetooptics,nanocomposite,nanoparticle,Faraday effect,thin film,plasmon resonance
更新于2025-09-16 10:30:52
-
Theoretical Study of GaN/BP van der Waals Nanocomposites with Strain-Enhanced Electronic and Optical Properties for Optoelectronic Applications
摘要： Construction of van der Waals (vdW) nanocomposites can advance two-dimensional (2D) materials with desired properties and significantly widen their applications. Based on first-principles calculations, we verify that a gallium nitride/boron phosphide (GaN/BP) vdW nanocomposite is a direct-gap semiconductor with type-I band alignment. The nanocomposite shows significant optical properties in the visible and near-ultraviolet regions. Additionally, the bandgap, band edge positions, and optical absorption of the GaN/BP nanocomposite can be tuned by in-plane biaxial strains. A biaxial tensile strain with a strength of 3% can induce the type-II band alignment in the GaN/BP nanocomposite, which results in effective separation of the photo-generated charge carriers. Meanwhile, the application of biaxial strain can also significantly enhance the optical absorption of the GaN/BP nanocomposite in the near-infrared and visible regions. Furthermore, we show that the adjustment of interlayer coupling is also an effective way to modulate the electronic and optical properties of the GaN/BP nanocomposite. Our studies reveal the potential application of the GaN/BP nanocomposite in optoelectronic devices.
关键词： first-principles calculations,optical absorption,strain engineering,band structure,GaN/BP nanocomposite
更新于2025-09-16 10:30:52
-
Hyperthermia Induced by Near-Infrared Laser-Irradiated CsWO3 Nanoparticles Disintegrates Preformed Lysozyme Amyloid Fibrils
摘要： This research study attempts to prove the concept of the applicability of hyperthermia to treating the lysozyme amyloid fibrils (LAF)’s self-assembled fibrillary aggregates by a feedback-modulated temperature controller ranging from 26 °C to 80 °C, and separately, by near-infrared (NIR) laser-irradiated cesium tungstate (CsWO3) nanoparticle (NPs). The dependence of the final morphology of the amyloidal assembly on external heating and the photothermal effect of the NPs on treating the fibrillary assembly were investigated and analyzed. Experimentally, atomic force microscopy (AFM), optical stereoscopy, and scanning electron microscopy (SEM) were used primarily to ensure mutual interaction between LAF and NPs, optically elucidate the surface contour and final fibrillary assembly upon the influence of thermal treatment, and further reveal fine-details of the optical samples. Finally, conclusive remarks are drawn that the fibrillary structures doped with the NPs exhibit an increasing degree of unique orthogonality. As the temperature rises, utter deformation of the dendritic structures of fibrillary assemblies at 70 °C was found, and NIR laser-irradiated CsWO3 NPs have been demonstrated to be useful in topically destructing pre-assembled LAFs, which may be conducive to the future development of neurodegenerative therapeutic techniques.
关键词： neurodegenerative diseases,self-assembled nanocomposite,lysozyme amyloid fibrils,hyperthermia,cesium tungsten oxide nanoparticles
更新于2025-09-16 10:30:52