Highly oriented ZnO nanorod arrays were successfully prepared on the indium tin oxide （ITO） substrate using a galvanostatic electrodeposition method. The ITO substrate was pretreated with ZnO nanoparticles via simpl...Highly oriented ZnO nanorod arrays were successfully prepared on the indium tin oxide （ITO） substrate using a galvanostatic electrodeposition method. The ITO substrate was pretreated with ZnO nanoparticles via simple low-temperature solution route. The crystallinity, microstructure of surface, and optical properties of the obtained ZnO were characterized by X-ray diffraction, scanning electron microscope, and transmittance spectrum. The results indicate that the average diameter of ZnO nanorod arrays is about 30 nm, and the narrow size distribution ranges from 20 to 50 nm. The nanorod arrays are growing along wavelength of incident is over 380 nm, the ZnO nanorod arrays growth mechanism of the nanorod arrays was discussed. [001] direction with an orientation perpendicular to the substrate. When the show a high optical transmission of above 95%. Furthermore, the possible展开更多
A facile and rapid electrodeposition route was developed to controllably synthesize well-aligned ZnO nanorod arrays on diverse substrates, such as seed-layer pre-formed, pristine indium tin oxide （ITO） and Si, using...A facile and rapid electrodeposition route was developed to controllably synthesize well-aligned ZnO nanorod arrays on diverse substrates, such as seed-layer pre-formed, pristine indium tin oxide （ITO） and Si, using Zn（NO3）2·6H2O and hexamethylenetetramine （HMT） as the precursors. X-ray diffraction （XRD） and transmission electron microscopy （TEM） results indicated that seed-layer pre-modified of ZnO nanorod arrays （ZNRs） possessed single crystalline, a wurtzite crystal structure with preferential growth orientation along [0001] direction. The ZNRs on pre-modified ZnO seed-layer （ZSL） had diameters of 30-50 nm, and aligned vertically to the substrates. ZNRs on ZSL/ITO substrate exhibited a high transmittance （above 80%） in visible wavelength range and the red-shift of band gap energy. An electrochemical reaction model was proposed to explain the growth process of ZnO nanorods. Importantly, the rapid synthesis of ZNRs provided the feasibility of preparation of SERS （surface enhanced Raman scattering） nanocomposite within shorter time by a subsequent electrochemical etching.展开更多
Dual-color(blue and green) InGaN/GaN nanorod light-emitting diodes(LEDs) with three different nanorod diameters are fabricated. Enhancement of luminescence intensity per area is observed in blue and green wells,to var...Dual-color(blue and green) InGaN/GaN nanorod light-emitting diodes(LEDs) with three different nanorod diameters are fabricated. Enhancement of luminescence intensity per area is observed in blue and green wells,to varying degrees. When the diameter is 40 nm, it sharply decreases, which could be explained by the sidewall nonradiative recombination. Time-resolved photoluminescence is conducted to study the carrier lifetime. High recombination rate is observed in nanorod arrays, and is an order of magnitude less than that of the planar LED.When the diameter is 40 nm, the nonradiative lifetime decreases, and this explains the decrease of intensity. The3 D-FDTD simulations show the enhancement of light extraction out of geometry structure by calculating the transmittance of the nanorod arrays.展开更多
Large quantity growth of ZnO nanorods is achieved by oxidation of Zn powders with catalyst free method.The products are characterized using X ray diffraction,scanning electron microscopy,transmission electron micro...Large quantity growth of ZnO nanorods is achieved by oxidation of Zn powders with catalyst free method.The products are characterized using X ray diffraction,scanning electron microscopy,transmission electron microscopy and photoluminescence spectroscopy.The as grown nanorods are structurally uniform with diameter ranging from 60 to 150nm and lengths of up to 5-8μm,and they are single crystalline in nature with growth direction parallel to .Room temperature photoluminescence spectrum of the nanorods shows a strong and sharp UV emission band at 385 nm and a weak and broad green emission band at 495 nm.The vapor solid model is also proposed to explain the growth behavior of ZnO nanorods in our synthesis process.展开更多
基金the National Natural Science Foundation1 of China (No. 50528404)the National High-Tech Research and Development Program of China (No. 2006AA03Z224)
文摘Highly oriented ZnO nanorod arrays were successfully prepared on the indium tin oxide （ITO） substrate using a galvanostatic electrodeposition method. The ITO substrate was pretreated with ZnO nanoparticles via simple low-temperature solution route. The crystallinity, microstructure of surface, and optical properties of the obtained ZnO were characterized by X-ray diffraction, scanning electron microscope, and transmittance spectrum. The results indicate that the average diameter of ZnO nanorod arrays is about 30 nm, and the narrow size distribution ranges from 20 to 50 nm. The nanorod arrays are growing along wavelength of incident is over 380 nm, the ZnO nanorod arrays growth mechanism of the nanorod arrays was discussed. [001] direction with an orientation perpendicular to the substrate. When the show a high optical transmission of above 95%. Furthermore, the possible
基金supports of the project from the National Basic Research Program of China (973 Program,No.2011CB302103)the National Natural Science Foundation of China (Nos.11174001 and 11174286)the Natural Science Foundation of Anhui Province,China (No.11040606M62)
文摘A facile and rapid electrodeposition route was developed to controllably synthesize well-aligned ZnO nanorod arrays on diverse substrates, such as seed-layer pre-formed, pristine indium tin oxide （ITO） and Si, using Zn（NO3）2·6H2O and hexamethylenetetramine （HMT） as the precursors. X-ray diffraction （XRD） and transmission electron microscopy （TEM） results indicated that seed-layer pre-modified of ZnO nanorod arrays （ZNRs） possessed single crystalline, a wurtzite crystal structure with preferential growth orientation along [0001] direction. The ZNRs on pre-modified ZnO seed-layer （ZSL） had diameters of 30-50 nm, and aligned vertically to the substrates. ZNRs on ZSL/ITO substrate exhibited a high transmittance （above 80%） in visible wavelength range and the red-shift of band gap energy. An electrochemical reaction model was proposed to explain the growth process of ZnO nanorods. Importantly, the rapid synthesis of ZNRs provided the feasibility of preparation of SERS （surface enhanced Raman scattering） nanocomposite within shorter time by a subsequent electrochemical etching.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61505197 and 61334009the National Science and Technology Major Project under Grant No 2017YFB0403803
文摘Dual-color(blue and green) InGaN/GaN nanorod light-emitting diodes(LEDs) with three different nanorod diameters are fabricated. Enhancement of luminescence intensity per area is observed in blue and green wells,to varying degrees. When the diameter is 40 nm, it sharply decreases, which could be explained by the sidewall nonradiative recombination. Time-resolved photoluminescence is conducted to study the carrier lifetime. High recombination rate is observed in nanorod arrays, and is an order of magnitude less than that of the planar LED.When the diameter is 40 nm, the nonradiative lifetime decreases, and this explains the decrease of intensity. The3 D-FDTD simulations show the enhancement of light extraction out of geometry structure by calculating the transmittance of the nanorod arrays.
文摘Large quantity growth of ZnO nanorods is achieved by oxidation of Zn powders with catalyst free method.The products are characterized using X ray diffraction,scanning electron microscopy,transmission electron microscopy and photoluminescence spectroscopy.The as grown nanorods are structurally uniform with diameter ranging from 60 to 150nm and lengths of up to 5-8μm,and they are single crystalline in nature with growth direction parallel to .Room temperature photoluminescence spectrum of the nanorods shows a strong and sharp UV emission band at 385 nm and a weak and broad green emission band at 495 nm.The vapor solid model is also proposed to explain the growth behavior of ZnO nanorods in our synthesis process.
基金Project (21171027) supported by the National Natural Science Foundation of ChinaProject (K1001020-11) supported by the Science and Technology Key Project of Changsha City, ChinaProject ([2010]70) supported by Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province, China
