- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Synthesis, characterization and DFT analysis of new phthalocyanine complexes containing sulfur rich substituents
摘要： Nine new tetrasubstituted metallophthalocyanines (MPc) bearing sulfur rich substituents on peripheral positions were synthesized and fully characterized. The new MPc compounds contain Co2+, Ni2+ and Cu2+. The photochemical and electrochemical properties of the new molecules were investigated. In addition to this investigation, a comparative study took place on the effect of the type of terminal ligand on properties of the MPc compound. Theoretical studies (DFT) were, also carried out in order to support the corresponding experimental results.
关键词： Cobalt,Copper,Nickel,Microwave synthesis,Phthalocyanines,DFT calculations
更新于2025-09-23 15:23:52
-
Scandium Molybdate Microstructures with Tunable Phase and Morphology: Microwave Synthesis, Theoretical Calculations, and Photoluminescence Properties
摘要： In this paper, scandium molybdate microstructures have been prepared from solution via a microwave heating method. By controlling the experimental parameters such as molar ratio of reagent and reaction time, scandium molybdates with tunable phase and diverse morphologies including snowflakes, microflowers, microsheets, and branched spindles were obtained. The density of states and surface energies of Sc2Mo3O12 were primarily studied from first-principles calculations. An indirect band gap of 3.56 eV was observed for crystalline Sc2Mo3O12, and the surface energies of various facets were determined to be 0.27–0.91 J/m2. The influence of n(Sc3+):n(Mo7O24 6?) (short for Sc/Mo) molar ratio was systematically investigated and well-characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and UV–vis absorption spectroscopy (UV–vis). Results indicate that the Sc/Mo molar ratio has a great effect on the phase and morphology. Diffuse reflection spectra (DRS) revealed the Egap can be readily tuned from 3.69 to 4.16 eV, which is in accordance with the theoretical result. The photoluminescence (PL) properties of Eu3+-doped Sc2Mo3O12 were discussed. This facile synthesis strategy could be extended to the synthesis of other molybdates.
关键词： photoluminescence,morphology control,microwave synthesis,scandium molybdate,density functional theory
更新于2025-09-23 15:23:52
-
Investigation of Microwave Irradiation Procedure for Synthesizing CdSe Quantum Dots
摘要： In recent years, microwave heating techniques for quantum dot (QD) synthesis have come to supplement the typical hot-injection methods. In addition to increasing control and replicability, microwave synthesis can be up-scaled to industry standards, an advantage that increases its lucrativeness. This study depicts a strategy to take a hot-injection procedure for cadmium selenide (CdSe) QD synthesis that is safe enough for undergraduate research labs and adapt it to an easier, more energy-efficient microwave synthesis method. Additionally, this study details successes in synthesizing these QDs, along with some challenges, limitations, and peculiarities. For future users of this method, it is recommended to keep holding temperatures between 170°C and 240°C to achieve the highest monodispersity of CdSe QDs while also avoiding confounding effects, such as wide-spectrum photoluminescence and bulk CdSe precipitation.
关键词： microwave synthesis,photoluminescence,hot-injection method,quantum dots,CdSe
更新于2025-09-23 15:19:57
-
Oxygen doped MoS <sub/>2</sub> quantum dots for efficient electrocatalytic hydrogen generation
摘要： In this study, we report an oxygen-doped MoS2 quantum dot (O–MoS2 QD) hybrid electrocatalyst for the hydrogen evolution reaction (HER). The O–MoS2 QDs were prepared with a one-pot microwave method by hydrazine-mediated oxygen-doping. The synthetic method is straightforward, time-saving, and can be applied in large scale preparation. Ultra-small O–MoS2 QDs with the average size of 5.83 nm and 1–4 layers can be uniformly distributed on the surface of reduced graphene oxide (RGO). Benefited from the unique structure and the doping effect of oxygen in the MoS2 QDs and the great number of active sites, the O–MoS2 QD hybrid displayed outstanding electrocatalytic performance toward HER. A low overpotential of 76 mV at 10 mA/cm2 and a Tafel slope of 58 mV/dec were obtained in an acidic solution toward HER. Additionally, the resultant O–MoS2 QD hybrid also exhibited excellent stability and durability toward HER, displaying negligible current density loss after 1000 cycles of cyclic voltammetry. The design and synthesis of the electrocatalyst in this work open up a prospective route to prepare active and stable electrocatalysts toward substituting precious metals for hydrogen generation.
关键词： electrocatalytic hydrogen generation,oxygen-doped MoS2 quantum dots,microwave synthesis,reduced graphene oxide,hydrogen evolution reaction
更新于2025-09-19 17:13:59
-
BWO nano-octahedron coupled with layered g-C3N4: An efficient visible light active photocatalyst for degradation of cationic/anionic dyes, and N2 reduction
摘要： The challenges like the removal of organic pollutants from the wastewater, and photocatalytic reduction of N2 using solar energy are achievable by stable, low cost, and a visible light active semiconductor mediated photocatalysis. A novel 0.4BWO/g-C3N4 heterostructure achieves excellent degradation of cationic/anionic dyes and N2 reduction under visible light illumination. The 0.4BWO/g-C3N4 exhibits 99.8% degradation efficiency towards the degradation of rhodamine B (RhB), which is 2.2-fold compared to commercial catalyst Degussa P25. 0.4BWO/g-C3N4 composite also efficiently degraded AV7, IC, DB 71 dyes and photo-reduce N2 to NH3. The incorporation of BWO nano-octahedron into the g-C3N4 network suppress the recombination of photogenerated electron-hole pairs and follow Z-scheme electron transfer pathway in 0.4BWO/g-C3N4 heterostructure. The notable separation of electron-hole pairs is well described by photoluminescence, time-resolved fluorescence, and impedance spectroscopy study. The finding presented here provides new insight into typical design and engineering of a stable and visible light active heterostructure for degradation of dyes and N2 reduction.
关键词： Photocatalyst,N2 reduction,Bi3.84W0.16 O6.24,Microwave synthesis,Dye degradation
更新于2025-09-16 10:30:52
-
Microwave-Assisted Synthesis and Assembly of Hyperbranched supra Quantum Dot CdE (E = S, Se, Te) Nanocrystals
摘要： Dichalcogenides are alternatives for synthesis of nano metalchalcogenides which provides a variety of precursors with different reactivities. Using disulfide, diselenide and ditelluride and their mixtures, metalchalcogenide nanocrystals (NCs) in which structures vary from spherical NCs with diameters of ~4 nm to large, hyperbranched NCs with diameters approaching 200 nm are synthesized. Study of the effects of the reaction temperature, concentration and ratio of reactants shows that hyperbranched supra quantum dots (HSQDs) form in three steps: nucleation, aggregation and kinetically-controlled growth. By tuning the concentration of precursors and reaction temperature, both aggregation and growth can be modulated and tetrapod NCs with arms of tunable length and thickness can be prepared. The more reactive precursor forms small NCs which work as a platform for formation of the arms from the less reactive precursor, providing controlled growth on the more reactive facets. By controlling the precursor ratio, the composition of the HSQDs can be controlled.
关键词： dichalcogenides,Microwave synthesis,asymmetric nanocrystals,oriented attachment
更新于2025-09-11 14:15:04
-
Transparent Heater Based on Al,Ga Co-doped ZnO Thin Films
摘要： Al, Ga co-doped ZnO thin films were deposited on to glass substrates by aerosol assisted chemical transport (AACT) and were studied for application as transparent thin film heaters. The film thickness was around 400 nm after 60 min of AACT deposition; this gave a sheet resistance of 142.5 ?/sq, which corresponded to a resistivity of 5.7 x 10-3 ?.cm. The thin films exhibited a maximum transmittance of 90% in the visible region. A mean temperature of 132.3 oC was reached after applying a voltage of 18 V for 10 min, giving a power consumption of 2.11 W. These results could provide a possibility to use Al, Ga co-doped ZnO thin films as transparent heaters to replace the more expensive indium tin oxide.
关键词： Transparent conducting oxides,microwave synthesis,thin film heater
更新于2025-09-09 09:28:46