- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Morphological Modification and Analysis of ZnO Nanorods and Their Optical Properties and Polarization
摘要: We report on the effect of the morphological modification on optical properties and polarization of ZnO nanorods (NR). Here, the morphology and structure of the ZnO NR were modified by introducing different annealing temperatures. The increase of length and diameter and change in density of the ZnO NR were clearly observed by increasing the annealing temperature. We found that the samples show different oxygen vacancy (VO) and zinc interstitial (ZnI) concentrations. We suggest that the different concentrations of VO and ZnI are originated from morphological and structural modification. Our results reveal that optical absorption and polarization of ZnO NR could be enhanced by producing a high concentration of VO and ZnI. The modification of VO and ZnI promotes a decrease in the band gap and coexistence of high optical absorption and polarization in our ZnO NR. Our findings would give a broad insight into the morphological modification and characterization technique on ZnO NR. The high optical and polarization characteristics of ZnO NR are potential for developing the high-performance nanogenerator device for multitype energy harvesting.
关键词: optical properties,polarization,annealing temperature,ZnO nanorods,morphological modification
更新于2025-09-11 14:15:04
-
Facile Synthesis of Carbon Nanotubes Covalently Modified with ZnO Nanorods for Enhanced Photodecomposition of Dyes
摘要: Utilizing a one-pot solvothermal procedure novel one-dimensional zinc oxide-carbon nanotube nanohybrids (ZnCT) were synthesized in alcohol-alkali solution, free of catalytic assistance. The ZnCT hybrids were prepared through covalent modification of zinc oxide nanorods (ZnO NRs) with functionalized carbon nanotubes (f-CNTs). The morphology and microstructure of as-prepared ZnCT hybrids were characterized by scanning electron microscopy (SEM), powder X-ray diffraction, Raman, X-ray photoelectron and UV-vis absorption spectroscopies. SEM images of the ZnCT hybrids indicated that the ZnOethanol NRs grew longer along the vertical radial (0001) surface and aggregated to a lesser extent than the analogous ZnOmethanol NRs. Photodegradation analysis showed that the off-white ZnCTethanol hybrid with ascendant UV-visible light absorption had displayed superior photocatalytic activity towards Rhodamine B (RhB) dyes than either pure ZnOethanol, ZnOmethanol NRs or ZnCTmethanol hybrid, among which the photocatalytic activity of ZnOethanol NRs was better than that of ZnOmethanol NRs. Raman and X-ray photoelectron spectroscopy analyses confirmed a strong interaction between f-CNTs and ZnOethanol NRs in ZnCTethanol hybrid, in which Zn ions were chemically bonded to negatively charged oxygen-containing groups at the graphene-like surface of f-CNTs. The enhanced separation lifetime of the photogenerated electron-hole observed by surface photovoltage and photocurrent measurements of the ZnCTethanol hybrid was attributed to the efficient covalent linking of Zn-O-C and close contact configuration between the f-CNTs and ZnOethanol NRs. Further controlled photodegradation and electron spin resonance (ESR) analyses revealed that the photodegradation of RhB dyes resulted from photogenerated holes, and radical species, such as ?O2?、?OH?, which were formed in-situ. Details of the photocatalytic mechanism were also explored herein.
关键词: Solvothermal synthesis,ZnO nanorods,Carbon nanotubes,Dyes,Photodegradation
更新于2025-09-10 09:29:36
-
Improved Gas Sensing Performance of ALD AZO 3-D Coated ZnO Nanorods
摘要: This paper reports an enhancement on the sensing performance of ZnO nanorod ethanol sensors with a new approach by utilizing nested coatings of Aluminum doped ZnO (AZO) thin films by Atomic Layer Deposition (ALD) technology. ZnO nanorods were grown by the hydrothermal method with the ZnO seed layer synthesized on Silicon wafers by ALD. To enhance the sensing performance of ZnO nanorod ethanol sensors, multiple coated AZO thin film 3-D coatings were deposited on the surface of the intrinsic ZnO nanorods by ALD. To investigate the sensing performance of the ZnO nanorods sensor for the detection of ethanol vapor, a gas sensor testing system was designed and built with a sealed reaction chamber and a temperature controller. The demonstrated sensing performance results include the sensing response comparison between ZnO nanorods before and after ALD coatings with AZO films at different temperatures and with various concentrations of input ethanol vapor. The response times and recovery times of ZnO nanorods before and after ALD coatings with AZO thin films were analyzed to investigate the sensing enhancement. The sensing response improvement peaks at 25?C room temperature with approximately 200% enhancement. However, the sensing response improvement decreases as a function of increasing operating temperature.
关键词: ZnO nanorods,gas sensor,ethanol vapor,ALD,AZO
更新于2025-09-09 09:28:46
-
Synthesis and Characterization of ZnO Nanorods as an Adsorbent for Cr(VI) Sequestration
摘要: Zinc oxide (ZnO) nanorods were fabricated through hydrothermal route and employed for the adsorption of Cr(VI) ions from aqueous medium. Zinc nitrate hexahydrate (Zn(NO3)2.6H2O) was used as a zinc precursor and Triton-x 100 was used as a capping agent. As synthesized ZnO nanorods were characterized by UV-visible spectroscopy (UV), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive X-Ray spectroscopy (EDX) techniques. The adsorption affecting parameters were investigated for maximum adsorption of Cr(VI) onto ZnO nanorods. The adsorption kinetics, isotherms, and thermodynamics were applied for adsorption mechanism evaluation. Maximum adsorption of Cr(VI) ions (250 mg/g) was achieved using 0.055 g/L ZnO dose at pH 2.0 for the contact time of 30 min. Pseudo-second-order kinetic model and Langmuir isotherm explained well the Cr(VI) adsorption onto ZnO nanorods. The Cr(VI) adsorption onto ZnO was spontaneous and endothermic in nature. In view of promising adsorption efficiency, ZnO nanorods could possibly be used for Cr(VI) ions removal from wastewater and also extendable for the adsorption of other heavy metals ions.
关键词: ZnO nanorods,Cr(VI) adsorption,hydrothermal synthesis,Cr(VI) removal,wastewater
更新于2025-09-09 09:28:46
-
Diffusion-Driven Al-Doping of ZnO Nanorods and Stretchable Gas Sensors Made of Doped ZnO Nanorods/Ag Nanowires Bilayers
摘要: A crystal-damage-free nano-doping method, which utilized the vacuum drive-in diffusion of Al into ZnO nanorods, was developed. In this method, vertical ZnO nanorod arrays that were grown by chemical bath deposition beforehand were deposited with Al thin film and subsequently heat-treated under a high vacuum. At an optimum condition, the surface Al atoms were completely diffused into ZnO nanorods, resulting in Al-doped ZnO nanorods. Stretchable gas sensors were fabricated by sequentially drop-casting Al-doped ZnO nanorods and silver nanowires on PDMS substrate. The resistance and response of the sensor could be optimized through the elaborate control of relative densities of Al-doped ZnO nanorods and silver nanowires. The sensor showed a high response of 32.3% to 10 ppm of NO2 gas at room temperature, even under a large strain of 30%. The NO2-sensing mechanism of Al-doped ZnO nanorods/silver nanowires bilayer sensors is discussed on the basis of synergistic interplay of Al-doped ZnO nanorods and silver nanowires.
关键词: Al-doped ZnO nanorods,Stretchable gas sensors,bilayers,drive-in diffusion,silver nanowires
更新于2025-09-09 09:28:46
-
AIP Conference Proceedings [Author(s) 4TH ELECTRONIC AND GREEN MATERIALS INTERNATIONAL CONFERENCE 2018 (EGM 2018) - Bandung, Indonesia (27–28 July 2018)] - Effects of Ag dopant and ultraviolet irradiation on structural properties of zinc oxide nanostructures
摘要: ZnO nanorods are promising UV light driven photocatalyst for the degradation of organic dyes. In this work, the effects of Ag dopant (0.02 to 0.1 mol%) and ultraviolet irradiation (0 to 6 min) on structural, optical and photocatalytic properties of zinc oxide nanorods were investigate. The Ag incorporation ZnO nanoraod have been grown on glass substrate by chemical solution deposition method. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis absorption spectroscopy (UV–vis). The XRD spectra of the Ag incorporation ZnO (Ag-ZnO) films indicate that Ag was incorporated in the wurtzite hexagonal crystal structure of ZnO and the crystallinity were enhanced with increasing of Ag amount as well as ultraviolet irradiation time. SEM micrographs of pure ZnO films revealed the uniform distribution of rod-like nanostructure of size of about 30-40 nm. Increasing Ag amount as well as irradiation time stimulated the optical properties of ZnO nanostructures. The photocatalytic activity of these nanostructures was evaluated by analysing UV irradiation degradation of methyl orange (MO) dye and it was observed that Ag-ZnO show significantly enhanced photocatalytic activity for degradation of MO, as compared to ZnO nanorods.
关键词: structural properties,ZnO nanorods,ultraviolet irradiation,Ag dopant,photocatalytic activity
更新于2025-09-04 15:30:14