- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Distarch Phosphate as a Matrix for the Generation of Quantum Dots
摘要： Generation of ZnS, CdS, CaS and MgS quantum dots (QDs) was attempted in the matrix of distarch phosphate, an anionic polysaccharide. Based on the analysis of FTIR spectra, thermograms and Differential Scanning Calorimetry, interactions of QDS with the matrix could be excluded. On generation of MgS QDs and also, to a certain extent, CaS QDs, hydrolysis of the salts generating these QDs took place. That process had an impact on the partial destruction of the matrix. Molecular weight and radii of gyration of the products showed that the generation of QDs was dependent on the properties of the matrix polysaccharide. The elasticity, plasticity and viscosity of the gels containing QDs were significantly lower than those of plain distarch phosphate. Generally these values changed with time similarly to gels free of QDs.
关键词： Biocomposites,Calcium sulfide,Cadmium sulfide,Magnesium sulfide,Zinc sulfide,Luminescent biodegradable foils
更新于2025-09-16 10:30:52
-
A Complex for Diagnostics of Laser Radiation of Semiconductor Targets Excited by a High-Frequency-Modulated Electron Beam
摘要： A complex of equipment for diagnosing the parameters of laser radiation of semiconductor targets, which are excited by high-frequency-modulated electron-beam pulses, is described. The ability to control the shape and duration of laser radiation in the picosecond range via high-frequency modulation of an accelerating-voltage pulse was demonstrated experimentally. A train of laser-radiation pulses with a maximum intensity of up to 2 × 107 W/cm2 was obtained on a cadmium sulfide target (λ = 525 nm).
关键词： picosecond range,cadmium sulfide,semiconductor targets,high-frequency-modulated electron-beam pulses,laser radiation
更新于2025-09-16 10:30:52
-
Effect of diode laser on physical properties of CdS thin films
摘要： In this study, Cadmium Sulphide (CdS) thin films are deposited on glass substrates by means of Spray Pyrolysis method to examine the influence of electromagnetic and optical features of these films by diode laser. Accordingly, samples are feasibly irradiated by laser pointer with a power of 500 mw and a wavelength of 532 nm at distance of 10 cm from the source during dissimilar exposure times of 10,20,30,40,50,60,70 and 80 minutes. The absorbance spectrums have been measured by UV-visible spectrophotometer under range of 190-1100 nm .Optical parameters such as transmission , reflection ,absorption coefficient (α), extinction coefficient (K), optical band gap (Eg), refractive index (n), and complex dielectric constants were evaluated from absorbance spectra. The results shows that the laser pointer irradiation cause decreased in transmittance (T), reflectance (R), absorption coefficient α, the extinction coefficient (K), refractive index (n) and the real and imaginary parts of dielectric constant and decrease in the value of the energy gap (Eg). In study of FTIR-spectrum of CdS films in different ratio of irradiation times, there was no change in the peak positions just bigger or smaller with increase in times of irradiation.
关键词： Cadmium Sulfide (CdS),Laser Irradiation,Electromagnetic and Optical Properties,Spray Pyrolysis,Thin Film
更新于2025-09-16 10:30:52
-
Monitoring of the Mechanism of Mn Ions Incorporation into Quantum Dots by Optical and EPR Spectroscopy
摘要： Synthesis of nanoparticles doped with various ions can significantly expand their functionality. The conditions of synthesis exert significant influence on the distribution nature of doped ions and therefore the physicochemical properties of nanoparticles. In this paper, a correlation between the conditions of synthesis of manganese-containing cadmium sulfide or zinc sulfide nanoparticles and their optical and magnetic properties is analyzed. Electron paramagnetic resonance was used to study the distribution of manganese ions in nanoparticles and the intensity of interaction between them depending on the conditions of synthesis of nanoparticles, the concentration of manganese, and the type of initial semiconductor. The increase of manganese concentration is shown to result in the formation of smaller CdS-based nanoparticles. Luminescent properties of nanoparticles were studied. The 580 nm peak, which is typical for manganese ions, becomes more distinguished with the increase of their concentration and the time of synthesis.
关键词： manganese,electron paramagnetic resonance (EPR),nanoparticles,quantum dots,zinc sulfide,cadmium sulfide,luminescence
更新于2025-09-12 10:27:22
-
The size dependence of optical properties in colloidal ZnxCd1-xS:Mn quantum dots in gelatin
摘要： Size-selected colloidal ZnxCd1-xS quantum dots were successfully prepared by aqueous synthesis in gelatin. Quantum dots with an average size of a few nanometers were obtained by changing the synthesis conditions such as the amount of precursors and temperature. Variation of the composition and size of particles leads to a change in the optical, in particular, luminescent characteristics of quantum dots. Estimation of particle sizes were performed by several methods based on X-Ray diffraction and optical data. The mechanisms of trap state photoluminescence in ZnxCd1-xS quantum dots are proposed. Models of increasing / decreasing the photoluminescence intensity depending on the composition and particle size are presented.
关键词： zinc sulfide,quantum dots,luminescence,quantum size effect,aqueous synthesis,cadmium sulfide
更新于2025-09-12 10:27:22
-
Simultaneously efficient light absorption and charge transport of CdS/TiO2 nanotube array toward improved photoelectrochemical performance
摘要： CdS has been widely used to modify TiO2-based photoanodes for photoelectrochemical (PEC) water splitting. Due to the poor interface contact between chalcogenides and oxides, however, such CdS modified TiO2 materials usually exhibit inefficient separation and transport of charges, leading to an unsatisfactory efficiency during the PEC water splitting process. Addressing this issue, we herein report a CdS/TiO2 nanotube array (CdS/TNA) photoanode that was fabricated through a successive ion layer absorption and reaction (SILAR) method with an additional subsequent annealing. This post-annealing process is essential to enhance the interface contact between the CdS and the TNAs, resulting in an accelerated transfer of photogenerated electrons from the CdS to the TNAs. In addition, the post-annealing also improves the light absorption capability of the CdS/TNA photoanode. The simultaneous enhancement of charge transport and light absorption provided by the post-annealing is essential for improving the PEC performance of the CdS/TNA photoanode. The CdS/TNA photoanode obtained by this strategy exhibits a much enhanced PEC performance in water splitting, and its photocurrent density and solar-to-hydrogen conversion efficiency could reach 4.56 mA cm?2 at 1.23 V vs. reversible hydrogen electrode and 5.61%, respectively. This simple but effective route can provide a general strategy for obtaining high-performance oxide-based photoelectrodes.
关键词： Photoelectrochemical water splitting,Nanotube arrays,Titanium dioxide,Cadmium sulfide
更新于2025-09-12 10:27:22
-
Polydopamine nanospheres loaded with l-cysteine-coated cadmium sulfide quantum dots as photoelectrochemical signal amplifier for PSA detection
摘要： A sandwich-type photoelectrochemical (PEC) immunosensor was constructed for sensitive detection of prostate specific antigen (PSA). It was based on electrochemically reduced graphene oxide-TiO2 (ERGO-TiO2) as photoelectrochemical platform to immobilize capture antibody (Ab1). Then, quinone-rich polydopamine nanospheres (PDANS) loaded detection antibody (Ab2) and photocurrent signal label, L-cysteine-coated cadmium sulfide quantum dots (CdSQDs). ERGO-TiO2 displayed greatly improved photocurrent response to white light. CdSQDs conjugated with PDANS further amplified photocurrent signal because of the good conductivity of PDANS and ERGO. The increased photocurrent showed a linear correlation with PSA in the concentration range from 0.02 pg mL?1 to 200 ng mL?1 with the detection limit of 6.8 fg mL?1. It also revealed high selectivity and good stability.
关键词： Electrochemically reduced graphene oxide-TiO2,Polydopamine nanospheres,Photoelectrochemical immunosensor,L-cysteine-coated cadmium sulfide quantum dots,Prostate specific antigen
更新于2025-09-12 10:27:22
-
Solution-processed Zn <sub/><i>x</i> </sub> Cd <sub/> 1- <i>x</i> </sub> S Buffer Layers for Vapor Transport Deposited SnS Thin-film Solar Cells: Achieving High Open-circuit Voltage
摘要： As an alternative buffer material to CdS, ZnxCd1-xS buffer layers for vapor-transport-deposited SnS thin-film solar cells (TFSCs) were fabricated using the successive ionic layer adsorption and reaction (SILAR) method. Varying the Zn-to-Cd ratio resulted in a series of ZnxCd1-xS thin films with controllable bandgaps in the range of 2.40–3.65 eV. The influence of the Zn-to-Cd ratio on the cell performance was investigated in detail. The Zn0.34Cd0.66S buffer layer was found to be the optimal composition for SnS TFSCs, and a record open-circuit voltage (Voc) of 0.405 V was achieved with an efficiency of 3.72%, while the SILAR-CdS buffer layer rendered a Voc of 0.324 V. The improvement in Voc when using the Zn0.34Cd0.66S buffer layer was corroborated by the spike-type conduction band offset of 0.35 eV with the SnS absorber, as revealed by X-ray photoelectron spectroscopy analysis. In addition, minimized interfacial recombination at the SnS/Zn0.34Cd0.66S heterojunction was confirmed by temperature-dependent Voc analysis under illuminated conditions.
关键词： open-circuit voltage,successive ionic layer adsorption and reaction,thin-film solar cells,Tin monosulfide,buffer layer,zinc cadmium sulfide
更新于2025-09-11 14:15:04
-
Comparative activity of aqueous dispersions of CdS nanocrystals stabilized by cationic and anionic polyelectrolytes in photocatalytic hydrogen production from water
摘要： The results of a study on the photocatalytic activity of aqueous dispersions of Ni-doped CdS nanocrystals (NCs) covered with an amphiphilic polyelectrolyte (PE) shell, i.e., a polycation (NC-PC) or polyanion (NC-PA), are presented for the first time. The H2 evolution rate measured under identical conditions served as a measure of activity. The NC-PC and NC-PA samples were characterized by similar PE content (~40%) and monomodal size distribution. According to our calculations based on the NC dimensions and lattice parameters, about one macromolecule of the PE is required to stabilize one NC. The average hydrodynamic diameter of the NC-PC was found to be 1.5 times larger than that of the NC-PA due to the difference between their chemical structures and different abilities of ionogenic groups to dissociate. The photocatalytic activity of the PE-stabilized CdS nanocrystals was significantly influenced by the type of the PE, while the H2 evolution rate depended on the reducing medium used during the process. When the medium contained Na2S or when the PE-stabilized NCs were pre-treated with Na2S, the effect of the shell type was more pronounced and the activity of NC-PA was 2 to 14 times higher than that of NC-PC.
关键词： polyelectrolytes,nanocrystals,photocatalysis,cadmium sulfide,hydrogen evolution reactions,nickel
更新于2025-09-10 09:29:36
-
Growth and Characterization of Indium Oxide, Zinc Oxide and Cadmium Sulfide Nanowires by Vapor-Liquid-Solid Growth Technique
摘要： In this study, the growth of three important semiconductor nanowires, Zinc Oxide, Indium Oxide and Cadmium Sulfide nanowires using the vapor–liquid–solid (VLS) method has been investigated. Different growth recipes with different growth parameters were incorporated to synthesize high quality and long NWs. It attempts to provide precise growth recipes which lead to high quality of nanowires. The effect of different growth conditions such as growth temperature, carrier gas flow, presence of metal catalyst and growth time has been investigated. Also, to evaluate the crystal quality of the nanowires, photoluminescence (PL) spectra of the as grown nanowires were investigated.
关键词： Cadmium sulfide (CdS),Zinc Oxide,Nanowires,Indium Oxide,vapor liquid solid (VLS) growth
更新于2025-09-09 09:28:46