修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

过滤筛选

出版时间
  • 2018
研究主题
  • XRD
  • I-doped Bi2MoO6
  • XPS
  • Photocatalysis
应用领域
  • Nanomaterials and Technology
机构单位
  • Chiang Mai University
  • Prince of Songkla University
752 条数据
?? 中文（中国） ▾

  • High acetic acid sensing performance of Mg-doped ZnO/rGO nanocomposites

    摘要： Mg-doped ZnO/reduced graphene oxide (rGO) nanocomposites were synthesized using a facile and cost-effective sol-gel procedure to detect acetic acid vapor. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy, and photoluminescence (PL) analysis were utilized to characterize morphologies, compositions of the nanocomposites, and optical properties of the synthesized nanostructures. The gas sensing measurements of spin-coated Mg-doped ZnO/rGO thin films were carried out for a temperature range of 150–350 oC at various acetic acid vapour concentrations. It was found that the Mg-doped sample with 20 wt. %/v of GO solution concentration exhibited the response/recovery time of 60 s/35 s with the best response of ~200% for 100 ppm of acetic acid at 250 oC.

    关键词： Mg-doped ZnO/rGO,Gas sensor,Acetic acid,Nanoparticles

    更新于2025-09-23 15:23:52

  • Copper’s Role in the Photoluminescence of Ag1?xCuxInS2 Nanocrystals, from Copper-Doped AgInS2 (x ~ 0) to CuInS2 (x = 1)

    摘要： A series of Ag1?xCuxInS2 nanocrystals (NCs) spanning from 0 ≤ x ≤ ~1 was synthesized by partial cation exchange to identify copper’s contributions to the electronic structure and spectroscopic properties of these NCs. Discrete mid-gap states appear above the valence band (VB) upon doping AgInS2 NCs with Cu+ (small x). Density functional theory (DFT) calculations confirm that these mid-gap states are associated with the 3d valence orbitals of the Cu+ impurities. With increasing x, these impurity d levels gradually evolve to become the VB edge of CuInS2 NCs, but the highest-occupied orbital's description does not change significantly across the entire range of x. In contrast with this gradual evolution, Ag1?xCuxInS2 NC photoluminescence shifts rapidly with initial additions of Cu+ (small x) but then becomes independent of x beyond x > ~0.20, all the way to CuInS2 (x = 1.00). Data analysis suggests small but detectable hole delocalization in the luminescent excited state of CuInS2 NCs, estimated by Monte Carlo simulations to involve at most about four copper ions. These results provide unique insights into the luminescent excited states of these materials and they reinforce the description of CuInS2 NCs as “heavily copper-doped NCs” in which photogenerated holes are rapidly localized in copper 3d-based orbitals.

    关键词： silver indium sulfide,nanocrystal,cation exchange,Copper indium sulfide,copper-doped,photoluminescence

    更新于2025-09-23 15:23:52

  • Electrochromic performance of chromium-doped Co3O4 nanocrystalline thin films prepared by nebulizer spray technique

    摘要： Pristine and chromium (Cr)-doped tricobalt tetraoxide (Co3O4) thin films were grown on glass and FTO substrates by nebulized spray pyrolysis technique. The structural, optical and electrical properties of the pristine and Cr-doped Co3O4 films were characterized by X-ray diffraction, scanning electron microscopy, Raman, and four-probe method. The chemical environment of the elements present in the films was identified from energy dispersive X-ray analysis and X-ray photoelectron spectroscopy. The effect of chromium doping on optical constants is discussed in detail. The electrochromic studies reveal that better optical modulation (?T = 38.3%) and high coloration efficiency (CE = 47 cm2/C) were obtained for 6 at. % of Cr-doped Co3O4 film. The present work suggests that incorporation of Cr in Co3O4 will enhance its electrochromic performance.

    关键词： Nebulized spray pyrolysis,Electrochromism,Cr-doped Cobalt oxide,Optical properties

    更新于2025-09-23 15:23:52

  • Silk Fibroin-Based Films Enhance Rhodamine 6G Emission in the Solid State: A Chemical-Physical Analysis of their Interactions for the Design of Highly Emissive Biomaterials

    摘要： Described herein is the preparation of dye-doped films employing silk fibroin (SF) as a biomaterial, capable of preserving the optical properties of the monomeric dye in the solid state, a critical requisite for optical and biolaser applications. A comprehensive physical–chemical characterization is reported for SF films doped with Rhodamine 6G, an ideal candidate for photonics and optoelectronics. Fourier transform infrared spectroscopy (FTIR), circular dichroism (CD) and X-Ray diffraction (XRD) provide information on SF secondary conformation in the presence of rhodamine. UV–vis absorption spectra and exciton CD inform on the structure of encapsulated rhodamine, while changes in dye photophysical properties illuminate the molecular mechanism of the involved host–guest interactions. SF host environment inhibits rhodamine dimer formation, indicating that SF is an optimum matrix to keep rhodamine essentially monomeric at concentrations as high as 7 mm in the film. The relevant optical properties of these films and the easiness of their preparation, make these systems optimal candidates for innovative photonic technologies.

    关键词： FTIR,silk fibroin,dye-doped biomaterials,exciton coupled CD,fluorescence

    更新于2025-09-23 15:23:52

  • 24.5: Back-Channel-Etched a-IGZO TFTs with TiO <sub/>2</sub> :Nb Protective Layer

    摘要： A back-channel-etched (BCE) process for the fabrication of a-IGZO TFTs is demonstrated, in which conductive TiO2:Nb (TNO) thin film is used to serve as protective layer for the a-IGZO active layer. TNO film could excellently protect a-IGZO due to its ultra-small surface roughness. With treatment by N2O plasma + 200°C annealing, the conductive TNO can be converted into an insulator to serve as an in situ passivation layer. Besides, the TNO in the source–drain (S-D) region remain conductive due to the protection of S-D electrodes, which could be proved by the XPS results. Compare with the conventional device without TNO protective layer, the S-D parasitic resistance (RSD) of devices with 1 nm and 5 nm TNO is significantly reduced. The positive bias stress stability is improved as well for the devices with TNO in situ passivation layer.

    关键词： amorphous indium gallium zinc oxide (a-IGZO),Nb doped TiO2 (TNO),thin film transistors (TFTs),back-channel-etched (BCE) process

    更新于2025-09-23 15:23:52

  • Structural study of MgO and Mg-doped ZnO thin films grown by atomic layer deposition

    摘要： Pure MgO, 1 and 10 at% Mg-doped ZnO layers were grown by atomic layer deposition technique onto (001)-oriented α-Al2O3 and GaN substrates. The structure and the microstructure of the deposited layers were studied by TEM in detail. The pure MgO layer starts to grow with epitaxy with (100)-type defects that transforms to random orientation. In the 10 at% Mg-doped samples epitaxial cubic MgO buffer layer forms at the interface. This buffer layer helps the ZnO to grow epitaxially in the case of α-Al2O3 substrate forming a ZnO/MgO/c-plane α-Al2O3 hetero-structure showing higher mobility with lower carrier concentration, while in the case on GaN substrate the ZnO is strongly textured. Consequently for higher concentration Mg doping (with the formation of MgO buffer layer) α-Al2O3 is better choice to grow epitaxial ZnO layer. The 1 at% Mg-doping of the epitaxial ZnO layer grown onto GaN substrate was successfully implemented, while in the case of α-Al2O3 substrate a thin cubic MgO buffer layer forms. This shows that the success of low concentration Mg doping in ZnO largely depends on the choice of substrate material as well.

    关键词： Mg-doped ZnO,ALD,MgO,TEM

    更新于2025-09-23 15:23:52

  • Effect of operational parameters on the photocatalytic degradation of Methylene blue dye solution using manganese doped ZnO nanoparticles

    摘要： Photocatalytic degradation of aqueous solution of methylene blue dye under UV light illumination was studied by using manganese doped ZnO (Zn1-xMnxO, where x = 0.00, x = 0.02 and x = 0.05) nanoparticles as a photocatalyst. The nanophotocatalysts were synthesized by wet chemical co-precipitation method. The structural, morphological, and optical properties of the photocatalysts were done by X-ray diffraction (XRD), Scanning Electron microscope (SEM), Energy Dispersive X-Ray (EDX), photoluminescence (PL), Fourier Transform Infrared Ray (FTIR) and UV- visible spectroscopic techniques. An improved photocatalytic efficiency of ZnO was observed upon doping with Mn and 2% Mn-doped ZnO exhibited the highest photocatalytic activity among the doped samples. The effect of operating parameters such as amount of catalyst, the initial dye concentration, and initial pH on the rate of dye degradation using 2% Mn-doped ZnO was studied. Under the optimum operation conditions, approximately 99% of dye removal was achieved after 120 min of irradiation.

    关键词： Manganese doped ZnO,Photocatalytic activity,Methylene blue dye

    更新于2025-09-23 15:23:52

  • Copper-doped hybrid Agx–Auy@ZnO nanoparticles and their enhanced photocatalytic activities

    摘要： In this paper, we report on the simple polyol synthesis of copper-doped hybrid Agx–Auy@ZnO photocatalysts. The obtained samples have been characterized by X-ray diffraction, UV–Vis diffuse reflectance spectroscopy, transmission electron microscopy and an N2 adsorption study. The experiment results show that Ag, Au and Ag–Au alloy nanoparticles (NPs) successfully load onto the surface of the assembled Cu-doped ZnO. The photocatalytic performances of Cu-doped Agx–Auy@ZnO nanomaterials have been tested using diuron herbicide as a model contaminant under simulated solar light irradiation. The addition of Ag and/or Au nanoparticles to doped ZnO was strongly beneficial to the rate constant displaying a volcano-like pattern as a function of the Ag and Au content. A maximum pseudo-first-order rate constant of 18.55 × 10?3 min?1, 22.70 × 10?3 min?1 and 24.74 × 10?3 min?1 was achieved on Cu-doped Ag0.3@ZnO, Au0.5@ZnO and Ag0.5–Au0.3@ZnO respectively. The Cu-doped Ag0.5–Au0.3@ZnO bimetallic nanoparticles show the highest photocatalytic activity due to the synergistic effect by effective electron transfer.

    关键词： Hybrid photocatalyst,Copper-doped,Diuron,Water treatment,Polyol process,One pot,Zinc oxide,Gold,Photocatalysis,Solar light,Silver

    更新于2025-09-23 15:23:52

  • Polar surface dominated octagonal Sn doped ZnO nanowires and their room-temperature photoluminance properties

    摘要： Polar surface dominated Sn doped ZnO nanowires (NWs) with an octagonal shaped cross section have been fabricated by chemical vapor deposition method. The NWs grew along [01 0] direction, and were wrapped by non-polar surface (2 0) and polar surfaces (0001) and (1 1). Planar defects in (0001) plane were formed in the middle of the doped NWs, and strain concentration occurred around the planar defects, which might lower the energy in the wurtzite lattice and thus maintain polar surface dominated configuration. X-ray photoelectron spectroscopy (XPS) and Raman tests reveal that the concentration of Oxygen vacancy (VO) was significantly lowered after doping, which led to the reduced deep level emission (DLE).

    关键词： Polar surface,Photoluminance,Sn-doped ZnO Nanowires,Microstructure

    更新于2025-09-23 15:23:52

  • A novel P-doped Fe2O3-TiO2 mixed oxide: Synthesis, characterization and photocatalytic activity under visible radiation

    摘要： In this work, a novel P-doped Fe2O3-TiO2 mixed oxide was successfully prepared by a microwave assisted sol-gel method. The synthesized catalyst was characterized by N2 physisorption, SEM, XRD, XPS, and FTIR, UV–vis DRS, and PL spectroscopies. The iron and phosphorus content in the catalyst samples were quanti?ed by AAS and ICP-OES, respectively. The photocatalytic activity of P-doped Fe2O3-TiO2 powders were evaluated in the photocatalytic degradation of sulfamethazine (SMTZ). The Box Behnken design (BBD) and response surface methodology (RSM) were applied for modeling the e?ect and optimizing of the operational parameters levels on the degradation percentage of SMTZ. The complete degradation and mineralization percentage of 30% of SMTZ solution at pH 9 was achieved within 300 min of reaction, with the optimum P doping amount of 1.2 wt % and 1.25 g/L of catalyst loading. The 1.2 wt % P-doped Fe2O3-TiO2 mixed oxide showed considerably higher photocatalytic activity than Fe2O3-TiO2 or TiO2. This enhanced performance could be attributed to the small crystallite size, narrow band gap, high speci?c surface area and increased number of surface hydroxyls on TiO2 nanoparticles. Additionally, the stability and reusability of this catalyst was demonstrated during three cycles of SMTZ degradation.

    关键词： Enhanced surface area,Visible light activation,Box behnken design,Reusability,P-doped Fe2O3-TiO2 mixed oxide

    更新于2025-09-23 15:23:52