Y and Cd co-doped ZnO nanopowders were prepared via chemical precipitation method in order to modify the band gap and increase the luminescent intensity. The structures and optical properties of the as-synthesized sam...Y and Cd co-doped ZnO nanopowders were prepared via chemical precipitation method in order to modify the band gap and increase the luminescent intensity. The structures and optical properties of the as-synthesized samples were characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS） and photoluminescence （PL）. The effects of Y and Cd ions on the optical properties of the samples were studied. Doping of Y into ZnO evidently increases the intensity of UV emission, or co-doping of Y and Cd enhances the UV emission, narrows the band gap of ZnO and hence red shifts the UV emission at the same time. Therefore, Y and Cd co-doped ZnO nanopowders exhibit an intense violet emission in the room temperature PL spectrum, which could be a potential candidate material for optoelectronic applications.展开更多
Low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O nanopowders(NPs)would determine their practical application in purifying wastewater.In this contribution,ZnO NPs were scala...Low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O nanopowders(NPs)would determine their practical application in purifying wastewater.In this contribution,ZnO NPs were scalably synthesized via the simple reaction of Zn powder with H_2O vapor in autoclave.The structural,morphological and optical properties of the samples were systematically characterized by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectra,transmission electron microscopy,Micro-Raman,photoluminescence,and ultraviolet-visible spectroscopy.The as-prepared Zn O NPs are composed of nanoparticles with 100–150 nm in diameter,and have a small Brunauer-Emmett-Teller surface area of 6.85 m^2/g.The formation of Zn O nanoparticles is relative to the peeling of H_2 release.Furthermore,the product has big strain-stress leading to the red-shift in the band gap of product,and shows a strong green emission centered at 515 nm revealing enough atomic defects in Zn O NPs.As a comparison with P25,the obtained dust gray Zn O NPs have a strong absorbance in the region of 200–700 nm,suggesting the wide wave-band utilization in sunlight.Based on the traits above,the Zn O NPs show excellent photocatalytic activity on the degradation of rhodamine B(Rh-B)under solar light irradiation,close to that under UV irradiation.Importantly,the Zn O NPs could be well recycled in water due to the quick sedimentation in themselves in solution.The low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O NPs endow themselves with promising application in purifying wastewater.展开更多
基金Project(2010CB631001) supported by the National Basic Research Program of ChinaProject(20121098) supported by the Foundation from of Key Laboratory of Preparation and Applications of Environmental Friendly Materials,Ministry of Education,ChinaProject supported by Graduate Innovation Fund of Jilin University,China
文摘Y and Cd co-doped ZnO nanopowders were prepared via chemical precipitation method in order to modify the band gap and increase the luminescent intensity. The structures and optical properties of the as-synthesized samples were characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS） and photoluminescence （PL）. The effects of Y and Cd ions on the optical properties of the samples were studied. Doping of Y into ZnO evidently increases the intensity of UV emission, or co-doping of Y and Cd enhances the UV emission, narrows the band gap of ZnO and hence red shifts the UV emission at the same time. Therefore, Y and Cd co-doped ZnO nanopowders exhibit an intense violet emission in the room temperature PL spectrum, which could be a potential candidate material for optoelectronic applications.
基金the National Natural Science Foundation of China (21161016)the Natural Science Foundation of Jiangxi Province (20142BAB216013)+1 种基金Jiangxi Education Department Fund (KJLD14087, GJJ14714)Jiangxi Environmental Protection Department Fund ([2013]370)
文摘Low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O nanopowders(NPs)would determine their practical application in purifying wastewater.In this contribution,ZnO NPs were scalably synthesized via the simple reaction of Zn powder with H_2O vapor in autoclave.The structural,morphological and optical properties of the samples were systematically characterized by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectra,transmission electron microscopy,Micro-Raman,photoluminescence,and ultraviolet-visible spectroscopy.The as-prepared Zn O NPs are composed of nanoparticles with 100–150 nm in diameter,and have a small Brunauer-Emmett-Teller surface area of 6.85 m^2/g.The formation of Zn O nanoparticles is relative to the peeling of H_2 release.Furthermore,the product has big strain-stress leading to the red-shift in the band gap of product,and shows a strong green emission centered at 515 nm revealing enough atomic defects in Zn O NPs.As a comparison with P25,the obtained dust gray Zn O NPs have a strong absorbance in the region of 200–700 nm,suggesting the wide wave-band utilization in sunlight.Based on the traits above,the Zn O NPs show excellent photocatalytic activity on the degradation of rhodamine B(Rh-B)under solar light irradiation,close to that under UV irradiation.Importantly,the Zn O NPs could be well recycled in water due to the quick sedimentation in themselves in solution.The low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O NPs endow themselves with promising application in purifying wastewater.
