- 标题
- 摘要
- 关键词
- 实验方案
- 产品
过滤筛选
- 2019
- charge – discharge energy efficiency
- Lithium-ion battery
- degradation diagnosis
- photovoltaic surplus energy
- working electric vehicle
- Electrical Engineering and Automation
- Ritsumeikan University
-
mpg-C <sub/>3</sub> N <sub/>4</sub> /Ag <sub/>2</sub> O Nanocomposites Photocatalysts with Enhanced Visible-Light Photocatalytic Performance
摘要： To study the photocatalytic activity under visible light irradiation, a series of mesoporous graphitic carbon nitride (mpg-C3N4)/Ag2O photocatalysts were synthesized. The as-prepared photocatalysts were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption Brunauer-Emmett-Teller method (N2-BET), Fourier transform infrared spectroscopy (FT-IR), UV-vis diffuse reflectance spectra (DRS), and photoluminescence spectra (PL) methods to determine their phase structure, purity, morphology, spectroscopic and photoluminescence emission performance, respectively. Photocatalytic degradation of methyl orange (MO) aqueous solution under visible-light irradiation indicated that the mpg-C3N4/Ag2O-50 nanocomposite exhibited the best activity. The degradation rate of MO reached to 90.8% in 120 min onto the mpg-C3N4/Ag2O-50 nanocomposite, and as compared with the pure mpg-C3N4 and Ag2O samples, the photocatalytic activity of the mpg-C3N4/Ag2O-50 nanocomposite was greatly enhanced. The enhancement of photocatalytic activity was mainly ascribed to the enhanced visible-light absorption ability and the formation of p–n heterojunctions between counterparts of the nanocomposites, which promoted the generation and separation of charge carriers.
关键词： mpg-C3N4/Ag2O,MO Degradation,Photocatalytic Activity,Visible-Light Photocatalysis,p–n Heterojunctions
更新于2025-09-04 15:30:14
-
Fabrication of MnO2-Amberlite for Photocatalytic Degradation of Alizarin Red S under Visible Light
摘要： Alizarin red S is a common toxic dyestuff causes water pollution that disturbs biota life in river and seawater. This study attempts to apply MnO2 immobilized in amberlite matrix to degrade Alizarin red S under UV illumination. With regard to various stirring time of MnO2-amberlite (6, 12, 18, 24 and 30 h) at room temperature, the BET verification shows the18 h-stirring time of MnO2-amberlite possessed the largest surface area (65.11 m2/g for 0.032 g sample). A strong peak of Mn-O linkage at 588 cm–1 is shown in FTIR spectra of MnO2-amberlite at 18 h stirring. The XRD of MnO2-amberlite at 18 h-stirring time shows a characteristic peak cluster at 25° (2è) related to additional crystal structure due to collision mechanical effect. SEM imaging of pure amberlite and different stirring time of MnO2-amberlite are also investigated. The fabricated MnO2-amberlite successfully degrades Alizarin red S under 1 h UV illumination (265 nm) applying 18 h-stirring time.
关键词： Aqueous solution,Photocatalytic degradation,Alizarin red S,MnO2-Amberlite
更新于2025-09-04 15:30:14
-
Green Synthesis of Co <sub/>3</sub> O <sub/>4</sub> Nanorods for Highly Efficient Catalytic, Photocatalytic, and Antibacterial Activities
摘要： Cobalt oxide nanorods were successfully synthesized by a hot plate combustion method using the plant extract of Vitis vinifera. The plant extract as an alternative to toxic chemicals can be used generally as reducing and capping agents. The obtained nanorods were characterized by XRD, FT-IR, Raman, TEM, SAED, EDX, DRS, PL and VSM techniques for the structural, morphological, optical and magnetic properties. The XRD, FT-IR, Raman, EDX analysis confirmed the high purity of the sample. The TEM and SAED results showed the rod shape morphology of the sample. DRS and PL showed the band gap energy and emission at visible region. VSM showed the antiferromagnetic nature of the sample. The photocatalytic activities of the as-prepared cobalt oxide nanorods were investigated for the degradation of textile dying waste water. As per the standards of Indian pollution control board for industrial waste water let out into river bodies, the degradation reactions of waste water was found to be 250 mg/L at 150 min. Also, the same catalyst is used for the reduction of 4-nitrophenol and 4-nitroaniline using sodium borohydride as a reducing agent and it exhibits excellent reduction reaction, because of the high active surface sites. The time taken for the reduction reaction was 300 sec and 210 sec for 4-nitrophenol and 4-nitroaniline respectively. Also, the antibacterial activities towards the bacterial strains were studied and reported.
关键词： Cobalt Oxide,Antiferromagnetic,Antibacterial Studies,Catalytic Reduction,Vitis vinifera Plant Extract,Photocatalytic Degradation
更新于2025-09-04 15:30:14
-
Large Scale Synthesis of ZnO Nanostructures of Different Morphologies through Solvent-free Mechanochemical Synthesis and their Application in Photocatalytic Dye Degradation
摘要： Well crystalline, near-stoichiometric zinc oxide nanostructures of different morphologies are fabricated in large scale, utilizing a simple, cost effective mechanochemical synthesis in absence of solvent. Effects of ionic and nonionic surfactants along with the concentration of hydrolyzing agent on the evolution of nanostructure morphology have been studied. It has been observed that while a cationic surfactant such as Cetyltrimethylammonium Bromide (CTAB) favors the nanostructures to growth along their polar c-axis, a nonionic surfactant such as Polyvinylpyrrolidone (PVP) reduces their preferred c-axis growth. Increase of hydrolyzing agent in the reaction mixture enhances the growth rate of the nanostructures. The nanostructures have been tested for photodegradation of anionic dye molecules such as Methylene Blue (MB). All the nanostructures manifest high photocatalytic performance. Apart from morphology, the specific surface area, crystal plane orientation and the concentration of basic sites at surface are seen to contribute significantly to the photocatalytic performance of the zinc oxide nanostructures.
关键词： Mechanochemical Synthesis,Photocatalysis,Nanostructures,ZnO,Dye Degradation
更新于2025-09-04 15:30:14
-
Exciton-Induced Degradation of Hole Transport Layers and Its Effect on the Efficiency and Stability of Phosphorescent Organic Light-Emitting Devices
摘要： The effect of exciton-induced degradation of hole transport layers (HTLs) and its influence on efficiency and stability of phosphorescent organic light emitting devices (PhOLEDs) are investigated. In order to be able to isolate and study the effect of excitons on HTLs, UV illumination as a means to expose them to exciton stress is used. Results reveal that exciton stress of only the HTLs can lead to a significant deterioration in the electroluminescence external quantum efficiency and stability of PhOLEDs, revealing the detrimental role of exciton-induced degradation of HTLs in limiting the device performance. The creation of quenchers in HTLs and the diffusion of excitons from the HTL to the EML appear to play roles in this degradation mechanism. Observations reveal that exciton-induced degradation of HTLs more strongly impacts PhOLEDs than their fluorescent counterparts, revealing the more critical role that HTLs play in influencing their stability and pointing to the role of triplet excitons in this phenomenon. Observations also suggest that increasing the exciton stability of HTLs or reducing exciton lifetime in them can help increase device stability. The findings uncover a new degradation mode in PhOLEDs and provide key insights for device design for realizing better performance and stability.
关键词： electroluminescence efficiency,device stability,phosphorescent OLEDs,exciton-induced degradation,hole transport layers
更新于2025-09-04 15:30:14
-
Intrinsic correlation between electronic structure and degradation: from few layers to bulk black phosphorus
摘要： Black phosphorus (BP) has received much attention due to its fascinating properties, such as a high mobility and tunable band gap which covers the band gap lacuna between graphene and transition metal dichalcogenides. However, these advantages have been overshadowed due to the fast degradation of BP in ambient conditions. To overcome this obstacle, the degradation mechanisms should be unveiled with direct observation followed by a thorough analysis. Here, we reveal two sequential degradation processes and layer-dependent degradation rates of BP under dark conditions by scanning Kelvin probe microscopy (SKPM) measurements and theoretical modeling. The layer-dependent degradation is successfully interpreted with the oxidation model based on the Marcus-Gerischer theory (MGT). Under dark conditions, the electron transfer rate from BP to oxygen molecule depends on the number of layers that give different carrier concentrations. The oxidation rate is strongly dependent on the number of layers, and thus carrier concentrations. This suggests the possibility of stability improvement by carrier modulation. This work not only provides a deeper understanding of the degradation mechanism itself but also suggest new strategies for stable BP-based electronics design.
关键词： oxidation model,work function,degradation,black phosphorus,Marcus-Gerischer theory
更新于2025-09-04 15:30:14
-
Magnetic photocatalysts from industrial residues and TiO2 for the degradation of organic contaminants
摘要： In this study, magnetic photocatalysts were prepared with different levels of TiO2 supported on tar pitch and red mud (RM) (40, 60, 80Ti/C/RM), which were used as carbon (C) and iron sources, respectively. The characterization by TEM, SEM and energy dispersive X-ray spectrometry showed that the RM particles are distributed in the bulk and on the surface of the carbonaceous matrix, forming the C/RM composite. These characterizations also confirmed the presence of TiO2 particles agglomerated on the photocatalysts surface. XDR results showed that the goethite and hematite in the RM was reduced to Fe3O4 and elemental analysis and Raman spectroscopy confirmed the carbon matrix. The obtained photocatalysts showed high efficiency to discolor the remazol black B dye (RB5). The 60 and 80Ti/C/RM photocatalysts decolorized 99% of the RB5 dye in reaction with solar radiation, while sample 40Ti/C/RM discolored 83%. The reactions performed with UV light showed that the 40, 60 and 80Ti/C/UV photocatalysts, decolorized 36, 60, and 71% of the RB5 and reduce 13, 34 and 52% of total organic carbon (TOC), respectively. Magnetic separation was preceded and the characterizations of the magnetic (MF) and non-magnetic fraction (NMF) confirmed that about 25% of TiO2 did not fix in the 60Ti/C/RM photocatalyst. MF and NMF decolorized 70 and 80% of the RB5, respectively, at the photocatalytic reaction (UV light). Sedimentation kinetics showed that photocatalysts are separated faster from aqueous environment than pure TiO2.
关键词： Tar Pitch,Degradation,Red mud,Photocatalysis,Titanium Oxide
更新于2025-09-04 15:30:14
-
Photocatalytic activities using a nanocomposite of mesoporous SiO2 and CdInSe-graphene nanoparticles under visible light irradiation
摘要： The new novel ternary mesoporous SiO2/CdInSe-graphene composites with diameters of approximately 8.08 nm have been fabricated through a self-assembly method. All physical tests demonstrated that the CdInSe-graphene was successfully uniformly distributed onto the surface of the ordered mesoporous silica particles. The obtained mesoporous SiO2/CdInSe-graphene composites exhibited good photocatalytic activity for degradation of both cationic-anionic organic dye groups, as well as the decomposition of the representative phenol group of the compound under visible light irradiation. Moreover, the photocatalytic evolution of hydrogen was studied for establishing a wider application of the as-fabricated SiO2/CdInSe-graphene catalyst in the case of energy conversion. This work indicated that the combination of the mesoporous silica and CdInSe-graphene enables achievements such as an enhancement photocatalytic performance, which has potential in industrial waste management and energy conversion.
关键词： Dye decomposition,CdInSe nanoparticles,Graphene-based nanocomposite,Gallic acid degradation,Mesoporous silica,Hydrogen production
更新于2025-09-04 15:30:14
-
Photocatalytic Performance on Visible Light Induced ZnS QDs-MgAl Layered Double Hydroxides Hybrids for Methylene Blue Dye Degradation
摘要： Semiconductor hybrids based photocatalytic reaction is one of the prominent methods to treat wastewater, containing the organic pollutants. In the present work, we report the development of ZnS QDs-LDH hybrid structure for the photocatalytic treatment of methylene blue (MB) dye. The as-synthesized ZnS QDs-LDH hybrid structure was characterized by XRD, FESEM, HRTEM, EDX, XPS, and FTIR to analyze the formation, morphology and chemical structure. The UV-Vis DRS was used to investigate the optical absorption characteristics of the ZnS QDs-LDH hybrid. The photocatalytic performance of the as-prepared samples was investigated against the methylene blue dye molecule under UV-Vis light irradiation. The scavenging experiments were carried out in order to probe the radical formation by using EDTA, benzoquinone, and 2-proponal. The cycling experiments were performed to check the stability of the ZnS QDs-LDH hybrid photocatalyst after repeated photodegradation experiments.
关键词： ZnS Quantum dots,Layered double hydroxides,Photocatalytic activity,Methylene blue dye degradation,Water treatment
更新于2025-09-04 15:30:14
-
Effect of temperature on structural and optical properties of solvothermal assisted CdS nanowires with enhanced photocatalytic degradation under natural sunlight irradiation
摘要： Photocatalytic degradation of toxic dyes is an important topic across the globe. This paper reports the photocatalytic degradation of methylene blue (MB) dye using cadmium sulfide (CdS) nanowires as a photocatalyst under natural sunlight irradiation. The CdS nanowires were successfully synthesized by a solvothermal route using ethylenediamine as a solvent with a series of different reaction temperature from 160 to 200 °C for a fixed time of 24 h. Multiple characterization techniques were used to investigate the structural, morphology, optical and photocatalytic study of as-synthesized CdS samples. The XRD patterns reveal highly crystalline CdS nanomaterials with a hexagonal crystal structure. The FESEM and HRTEM observations clearly confirmed a large number of uniform nanowires grown in different directions and interconnected with each other. The stoichiometric ratio of Cd:S is almost 1:1, confirmed by EDS analysis. Room temperature PL spectra of CdS nanowires exhibit a narrow emission at a wavelength of 512 nm. The CdS nanowires synthesized at 200 °C shows the excellent photocatalytic performance with highest photodegradation efficiency has reached up to 98.75% within 20 min, under sunlight irradiation. The 93.06% and 89.10% photodegradation efficiency were observed in CdS nanowires synthesized at 180 °C and 160 °C, respectively. From these result, it is observed that the crystallite size and morphology of CdS nanowires are the influence factors for the photodegradation efficiency of MB dye. Furthermore, the mechanism of MB dye photodegradation using CdS nanowires was discussed. These CdS nanowires with high photocatalytic activity can be used for future in water pollutant degradation.
关键词： Hexagonal CdS,Solvothermal synthesis,MB dye degradation,Reaction temperature,Sunlight irradiation
更新于2025-09-04 15:30:14