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摘要：OLEDs have been recognized as charge-injection electroluminescent devices. Using suitable hole injection layer (HIL) can reduce the barrier of hole injection from the anode to the hole transport layer, improve the hole injection, decrease the driving voltage of the OLEDs and enhance the efficiency and stability of the OLEDs. In this article, the OLEDs with structure of ITO／HIL／NPB(40 nm)／Alq₃ (60 nm)／LiF (1 nm)/Al (100 nm), where the HIL is single MoO₃(5 nm) layer or composite Au(4 nm)/MoO₃(5 nm) layers, were reported. It was found that the OLEDs with the composite Au/MoO₃ HIL shows higher current density and luminance than those of the OLEDs with single MoO₃ HIL at the same driving voltage, which indicates that hole injection is improved by further introducing the 4 nm Au between ITO and MoO₃.  

摘要：Organic light-emitting devices (OLEDs) have various advantageous features, such as self-emission, high luminous efficiency, full-colour capability, wide viewing angle, high contrast, low power consumption, low weight, potentially large area colour displays and flexibility. So, they have attracted considerable interest due to their promising applications in flat-panel displays. Here, the effect of ZnO nanolayer on the efficiency of OLED is reported. ZnO nanolayer was introduced between 8-hydroxyquinoline aluminum (Alq₃) and N, N-bis-(1-naphthyl)-N, N-diphenyl-1, 1-biphenyl-4, 4-diamine (NPB) layers, and their influence on the device performance was investigated. When the 1.0 nm ZnO film is inserted, for an unoptimized device composed of indium-tin oxide (ITO)/NPB/ZnO/Alq₃/LiF/Al, the current efficiency is as high as 3.26 cd·A^-1. It is much higher than that of conventional device. The mechanism of performance enhancement was discussed. For the fabrication of the OLEDs, ITO (sheet resistance 30 Ω/□) glass, thoroughly cleaned was used. The routine cleaning procedures include ultrasonic agitation in acetone, ethanol, rinsing in de-ionized water, and isopropyl alcohol. After the oxygen plasma treatment in vacuum chamber, the substrates were loaded into a vacuum chamber with a base pressure of 4.0×10^-4 Pa. LiF, NPB, ZnO, Alq₃, and Al electrode were thermally deposited without breaking the vacuum, respectively. The deposition rate and film thickness were measured by a quartz oscillator connected to a frequency meter near the substrates during the deposition. In this study, we define the voltage as the operating voltage when emitted light is first detected. The level of light first resolved is around 1 cd/m² in our experimental setup. The current-voltage characteristics reported here were all measured in the forward bias voltage mode. In conclusion, it was found that the 1 nm thick ZnO layer can greatly improve the performance of the Alq₃ based organic light-emitting device. The improved efficiency of the device could be due to the ultrathin ZnO layer acting as the decreased holes injection into the emissive layer, which would made the number of electrons and holes injected into the emitter layer to be balanced.  

摘要：The light-emitting characteristics of microcavity organic light-emitting device (MOLED) is directly related to the structure of microcavity, MOLED can be simulated by using transfer matrix method according to the related calculation formula of microcavity device. Under the unchangeable circumstances of the total length of microcavity L=λ/2(λ is the center wavelength), this paper simulates and compares with the functions of composite light emitting EL when exciton is in different positions of microcavity. The result shows that peaks of electroluminescence spectrum are all in the 520 nm of designed center wavelength, the full wavelength of half maximum (FWHM) are all 17 nm. The peak intensity and integral intensity are the biggest when exciton is in the central area of microcavity. Because now the exciton is at the maximum position of the electric field which is in the microcavity, both sides became smaller and smaller when exciton deviates from this position. It illustrates that you have to make exciton at the best position of microcavity if you want to create an efficient MOLED.  

摘要：Organic light-emitting diodes (OLEDs) are of considerable interest in flat panel displays and ligh-ting applications due to their many advantages, however, only about 20% light generated from the organic layer in the devices can escape to external forward space due to total internal reflection effect. Therefore, many methods have been used to increase the outcoupling efficiency of the devices. In this article, a monolayer of polyethylene (PS) microspheres (MS) with diameter of around 3 μm was prepared by self-assembly method on microscope cover glass. The microlens-like structure was obtained by annealing the PS MS monolayer at 120 ℃ for around 20 min. The annealed PS MS monolayer was then optically coupled (by refractive-index-matched material) on the outside of an OLED, with structure of Glass/ITO(40 nm)/NPB(40 nm)/Alq₃ (60 nm)/LiF (1 nm)/Al (100 nm) as a light scattering layer. The OLEDs with the annealed monolayer of PS MS exhibit improved normal direction luminance and efficiency (about 9% at the current density of 50 mA/cm² and the luminance round 1 250 cd/m²) compared to the control devices, which indicated that part of the light confined within the glass substrates can be extracted to the external forward space through scattering effects of the annealed monolayer of PS MS.  

摘要：Na₂SO₄ : TbF₃ phosphors were prepared by heating pure natural thenardite with TbF₃ at 900 ℃ for 20 min in air. Their photoluminescence (PL) spectra were observed under vacuum ultraviolet (VUV)-ultra-violet (UV) light excitation at room temperature. We observed two emission series assigned to the electronic transitions from ⁵D₄ and ⁵D₃ to ⁷F_J(J = 6, 5, 4, 3 and 2) of Tb³⁺ in Na₂SO₄. The excitation spectrum was consisted of (1) strong bands assigned to the 4fⁿ→4f^n-15d transitions (186, 190 and 218 nm), (2) the host absorption (163, 200 and 240 nm) and (3) weak bands assigned to the forbidden f-f transitions of Tb³⁺. The relative excitation efficiency in VUV light region is increased with increase of TbF₃ contents in 0.3%~2.0% range, and the relative excitation efficiency of only the host absorption in UV light region is increased with increase of TbF₃ contents. This preparation method would be useful for creating new phosphors using pure natural minerals that cannot be synthesized artificially as host crystals.  

摘要：A novel blue-emitting phosphor LiCaPO₄ : Eu²⁺ for LEDs was prepared by high temperature solid-state reaction and its luminescent properties were investigated. The emission spectrum shows a single intense band centered at 470 nm, which corresponds to the 4f⁶5d¹→4f⁷ transition of Eu²⁺. Comparing with LiSrPO₄ : Eu²⁺ and NaBaPO₄ : Eu²⁺, the emission spectrum shows a red shift obviously. It is caused by the decrease of cationic radii which change the degree of Eu²⁺ energy splitting and affect the electron cloud expansion. The excitation spectrum is a broad band extending in 250~440 nm, which matches the emission of ultraviolet light-emitting diodes (UV-LEDs) well. The effect of doped Eu²⁺ content on the emission intensity of LiCaPO₄ : Eu²⁺ was also investigated. Different Eu²⁺ contents have little effort on the emission spectrum, but the emission intensity shows a great different. The emission intensity is enhanced with the increase of the Eu²⁺ content, and the optimal doping content is 5%. Concentration quenching occurs when the Eu²⁺ content is beyond 5%, as a result of multipole-multipole interaction. The LiCaPO₄ : Eu²⁺ phosphor is a potential blue-emitting phosphor for white-emitting LEDs.  

摘要：The LiSrPO₄ : Tb³⁺ green phosphor was synthesized by the general high temperature solid-state reaction and an efficient green emission under near-ultraviolet excitaion was observed. The X-ray diffraction pattern indicated that pure LiSrPO₄ : Tb³⁺ phosphor was obtained. Its luminescence properties were investigated and showed four major emission peeks locating at 490, 545, 585 and 622 nm, corresponding to the ⁵D₄→⁷F₆,⁵D₄→⁷F₅, ⁵D₄→⁷F₄ and ⁵D₄→⁷F₃ typical transitions of Tb³⁺ , respectively, and the strongest one appears at 545 nm. The excitation spectrum contains a broad band extending in 200~400 nm, which is coupled well with the emission of ultraviolet light-emitting diodes (UVLEDs). The influence of the doped content of Tb³⁺ ions on the emission intensity was also investigated and the concentration quench occurs when the doped content of Tb³⁺ ions is beyond 9%, which can be explained by electric multipole-multipole interaction according to Dexters theory. It was also found that the Ce³⁺ ions in the system can make the emission intensity of LiSrPO₄ : Tb³⁺ increase. The value of emission intensity reaches the maximum when the concentration of Ce³⁺ ions is 3%. In conclustion, the LiSrPO₄ : Tb³⁺ is a potential green-emitting phosphor for white LEDs.  

摘要：The characterizations of surface morphologies, crystal structures, and optical properties of the ZnO films prepared by a vapour-phase technique on different substrates were performed in this study. Scanning electron micro-scopy (SEM) data showed that larger ZnO particles are formed on the Au-covered Si substrates than those on Si substrates. X-ray diffraction (XRD) results indicated that hexagonal wurtzite ZnO films are grown on both Si(111) and Si(100) substrates though they present different diffraction peaks with hexagonal wurtzite structure, while appears no sphalerite structure. The ZnO films prepared on Au-coated Si substrates prefer to grow along with c-axis orientation. The PL spectra reveal only a narrow strong UV emission peak at about 389 nm (3.19 eV) in all the ZnO samples.  

摘要：ZnO/n-Si heterostructures were fabricated using pulsed laser deposition (PLD), and then samples were annealed at 500 ℃ (S1), 600 ℃ (S2), 700 ℃ (S3) and 800 ℃ (S4) at oxygen ambience for 1 h, respectively. ZnO film deposited on Si substrates usually forms into polycrystalline structure, leading to barrier at the ZnO grain boundary. The grain boundary has a great influence on photoelectricity of ZnO film, but so far as we known, there are no reports in detail about this aspect. In order to clarify the influence of grain boundary variation on the photoelectricity characteristics of ZnO films, we performed thermally stimulated current (TSC), current-voltage (C-V), X-ray diffraction (XRD) and ellipsometry measurements.The results showed that a deep level center located at E_C-0.24±0.08 eV is obtained by TSC in S1, which is related to an intrinsic defect. The surface states of the ZnO grains, which have acceptor behavior and capture electrons from defects, result in the formation of grain barriers. A neutral donor deep level center (D⁰) located at E_C-0.13±0.03 eV appears as the annealing temperature reaches to 700 ℃.It could be due to the D⁰ complex defect in grain boundary that has a relationship with high temperature oxygen treatment. Combined with XRD and ellipsometry results, it was evident that, after oxygen annealing, the microstructure of ZnO films is improved and the stoichiometric deviation which dominated the photoelectricity characteristics of the ZnO films.  

摘要：Na-N co-doped p-type ZnO ∶ (Na, N)] thin films were prepared on glass substrates by RF reactive magnetron sputtering and post-annealing techniques in the N₂O ambient. X-ray diffraction (XRD) measurements showed that all films possessed a good crystallinity with c-axis preferential orientation. After annealing, the intensity of the (002) diffraction peak and the value of 2θ increase and the FWHM decreases. Hall measurements showed that the electrical properties of ZnO ∶ (Na, N) films were improved after annealing and the p-type behavior was realized. The film annealed at 450 ℃ showed the lowest resistivity of 139.2 Ω·cm with a Hall mobility of 0.2 cm²·V^-1·s^-1 and a carrier concentration of 2.5×10¹⁷ cm^-3. XPS measurements showed that Na_Zn acceptor in ZnO ∶ (Na, N) is responsible for the p-type conductivity of the ZnO ∶ (Na, N). In addition, Na-N complex may exist in the films, which acts as acceptor. Detailed investigation is now in progress.  

摘要：Cu-doped ZnO films grown on Si (001) wafers and quartz substrates were prepared with a radio-frequency reactive magnetron sputtering method. X-ray diffraction, transmittance spectra, photoluminescence spectra, and calculation based on the density functional theory are used to analysis the crystal structure, optical properties, and band structure. All the Zn_1-xCu_xO films are highly (001) textured without any precipitated phase, and Cu dopants hardly change the c parameter of ZnO. In the transmittance spectra, there is ob-vious abnormal absorbability in near ultraviolet and visible area. Being consist with the calculation, the band gap of Zn_1-xCu_xO films decrease with the increasing Cu concentration. Significant reduction of the PL efficiency caused by Cu dopants is seen in PL spectra. The emission in near ultraviolet and visible area is found moves with increasing the Cu concentration, while the location of the main emission peak doesn't move. It is believed that the absorbability and the emission in near ultraviolet and visible area is related to the impurity levels caused by Cu dopants. And the calculation results that the Cu-3d states lie the entry of the forbidden band confirming our standpoint. We hope this study will be helpful for the understanding of optical properties of Cu-doped thin ZnO films.  

摘要：In recent years, zinc oxide (ZnO) has received much attention due to its potential applications in blue and ultraviolet devices. High quality and high efficiency p-type doping is still a big challenge for their studies and device applications. Zincblende ZnO is suggested to be one possible key to overcome this obstacle. Metastable thin zincblende ZnO film has been realized on GaAs(001), sapphire, and Pt(111)/Ti/SiO₂/Si(100) multilayered substrates using a ZnS buffer/interlayers for the growth. However, due to the very large lattice mismatching, silicon is not the idealist substrate for the epitaxial growth of single crystal ZnO, while a great variety of wurtzite ZnO nano-structures have been constructed on Si(001). In this work, a plasma assistant molecular beam epitaxy was employed to grow the zincblende ZnO directly on Si(001) substrate at room temperature, and the growth kinetics was simply explored. The samples were grown and post-annealed under modulated growth conditions. They were zincblende polycrystalline embedded with wurtzite subdomains revealed by in-situ scanning tunneling microscopy and X-ray diffraction measurements. Nano trapezoid columns were observed on the as-grown samples. Nanostructural rings and clusters were depicted during the surface evolution after annealing. Though the zincblende ZnO is quite stable in ambient conditions, the metastable phase can be realized only under some critical conditions, such as the initial stage of ZnO nucleation during the epitaxial growth. The wurtzite ZnO generally has a growth privilege over the zincblende ZnO. Since the silicon substrate has a cubic symmetry lattice, it could result in formation of the zincblende ZnO in square structure at the initial growth, especially under the very low epitaxial temperature, i.e. room temperature. With the increasing of the thin film thickness, the influence from the substrates decreases, then the growth turns to favor for more stable wurtzite structure. Thus, the samples became zincblende polycrystalline embedded with wurtzite subdomains. Though the surface experiences a series of evolutions under annealing, the investigations showed the phase transition from zincblende to wurtzite is not as remarkable as expected.  

摘要：It is important to control the orientation of ZnO film because many properties of ZnO film vary with its preferred orientation. Most of ZnO films ever reported are orientated towards c-axis. However, in the light-emitting application, nonpolar or semipolar ZnO films grown not along with c-axis are much preferable because the luminous efficiency of the c-axis orientated ZnO film is low due to the quantum confined Stark effect. Thus, the study of ZnO film grown along with other than c-axis is necessary. In this paper, ZnO films were fabricated on 304 stainless steel substrates by the cathodic electrodeposition in Zn(NO)₃ aqueous solution, and the influences of Zn²⁺ concentration and the current density on the preferred orientation of the ZnO film were studied. X-ray diffraction results showed that as Zn²⁺ concentration and the current density increases, the preferred orientation of ZnO film changes from (002) to (101) gradually. When Zn²⁺ concentration is 0.005 mol·L^-1 and the current density is 2.0 mA·cm^-2, or Zn²⁺ concentration is 0.05 mol·L^-1 and the current density is 0.5 mA·cm^-2, the prepared ZnO films are (002) preferred orientation. When Zn²⁺ concentration is 0.05 mol·L^-1 and the current density is 2.0 mA·cm^-2, the prepared ZnO film is (101) preferred orientation. The phenomenon can be explained based on the two-dimensional nuclei theory. When Zn²⁺ concentration or the current density is low, the supersaturation of ZnO around substrate is also low and the nucleation activation energy of two-dimensional (002) nuclei is lower than that of (101) nuclei, therefore ZnO film is (002) preferred orientation. When Zn²⁺ concentration and the current density is high, the supersaturation of ZnO is also high and the nucleation activation energy of (002) nuclei is higher than that of (101) nuclei, therefore ZnO film is (101) preferred orientation. The results suggested that orientation-controllable growth of the cathodically electrodeposited ZnO films can be achieved by adjusting Zn²⁺ concentration and the current density.  

摘要：Thin ZnO : Al(AZO)films were prepared on the quartz substrates by using rf magnetron sputtering method, and the effects of O₂/Ar ratio on the thickness, crystallization and conductivity of the thin films were investigated. Results shown that under a certain pressure, the films gain larger thickness and higher conductvity with increasing flow rate of Ar. The sample prepared in the pure Ar ambience can gain the lowest resistivity because of the high crystallization and large thickness. The thickness and resistivity is 2.06 μm and 2.66×10^-4 Ω·cm respectively. As shown by the results, we found that the high crystallization is the crucial factor for decreasing resistivity and the large thickness will decrease it as well.

  

摘要：The thin Ag : ZnO/SiO₂ (AZSO)composite films with Ag doped in ZnO layer were deposited on glass substrates by means of sol-gel method. The crystal structure, microstructure, transmission, absorbance and photoluminescent properties of the samples were characterized by XRD, SEM, UV-Vis and PL, respectively. And the properties of thin composite films under the influence of different Ag contents were also discussed. The results of XRD indicated that there are diffraction peaks of ZnO and Ag after annealed in air at 300 ℃. The results of SEM showed that the film is uniformity and compact, and two-layer structure can be observed from the cross-sectional micrographs. The results of UV-Vis indicated that as the content of Ag increasing, the absorption peaks have red shift and widen because of the electron transfer between Ag and ZnO and the particle size of Ag becoming larger. The transmission of the thin composite films weakens as increasing the content of Ag, and optical absorption edges move to short wavelength. And band gaps of the composite films diminish, too. The PL spectra shows that photoluminescent intensity of the films in the section of ultraviolet and visible region weakens with increasing the content of Ag, this is owed to the reduction of the hole concentration and the compensation of structural defects caused by the doping of Ag and Ags absorption at 440 nm.  

摘要：Al-doped ZnO (AZO) film has high transmittance in the visible region, low resistance and better stability, so AZO films have been actively investigated for potential applications in a variety of opto-electronic devices, such as solar cells, flat panel displays, transparent heat mirrors and organic light-emitting diodes. The properties of ZnO film are critically dependent on various deposition parameters, such as radio-frequency power, working gas pressure, and substrate temperature,and so on, Among these factors, the study of influence of rf power on film properties is important to build on the understanding of the relationship between film properties and process conditions. In this paper, using ZnO mixed with Al₂O₃(2%) as target, thin AZO films were prepared on glass substrates by radio frequency magnetron sputtering at different rf powers of 40,80,120,160 and 200 W. The influence of sputtering power on structure, optoelectronic properties, thickness and thermal stability of thin AZO films were investigated by XRD, UV-Vis spectrophotometer, four point probe and instrument level. It was found that the AZO thin films with hexagonal wurtzite structure have a (002) c-axis preferential orientation, and the intensity of the (002) peak increase as the increase of RF power. For all of the AZO thin films, the average transmittance of the visible light is above 80%. The sheet resistance decreases as the increase of RF power. The films deposited at 160 and 200 W show good thermal stability, which change of sheet resis-tance before and after heat treatment is about 13%. This high thermal stability indicated that AZO films can replace thin Sn-doped In₂O₃ (ITO) films applying in the touch screen.  

摘要：ZnO is an interesting wide-band-gap semiconductor material with a direct band gap of 3.37 eV at room temperature and it makes more attention to the ultraviolet (UV) optoelectronic devices, such as UV laser, optical waveguide, and exciton-related devices. Usually, an insufficient supply of oxygen in ZnO during growth precludes various applications. In order to overcome these difficulties and obtain a strong ultraviolet near band edge emission and a much weaker emission band correlated with deep-level defects, it is necessary to prepare a high-quality thin ZnO film. In this paper, different oxygen flow rates (30, 50 and 70 sccm) are introduced into the vacuum chamber and the influence of oxygen flow rate to the thin film quality is studied. It can be seen that thin ZnO films with strong c-axis preferred orientation are grown on single crystal silicon (111) and quartz (SiO₂) substrates by pulsed laser deposition (PLD) method. In the range of 30~70 sccm for oxygen flow rate, thin ZnO film fabricated under the condition of O₂ flow rate of 50 sccm has higher optical transmittance above 80%, higher O₂ content ~ 40.71%, higher growth rate ~252 nm, stronger ultraviolet near band edge emission and a weaker emission band correlated with deep-level defects.  

摘要：Li-doped ZnO nanorods was grown on n-Si (111) substrate by chemical vapor deposition. XRD pattern showed that the nanorods are pure wurtzite ZnO of hexagonal crystal structure without any other oxide, such as Li₂O. Hall effect experiment under Van der Pauw configuration showed that Li-doped ZnO nanorods behave the p-type conductivity with hole concentration of 6.72×10¹⁶ cm^-3 and a Hall mobility of 2.46 cm² ·V^-1·s^-1. A neutral acceptor- bound exciton emission (A°X) was confirmed by the measurements of temperature-dependent photoluminescence (PL) spectra. The optical acceptor energy level is calculated to be about 142 meV.  

摘要：Flower-like zinc oxide (ZnO) products were synthesized without any surfactants in the reaction of aqueous solution of zinc chloride and NaOH under stirring at 60 ℃. Detailed structural analysis showed that the flower-like structures consist of many nanorods, whose diameter is approximately 90 nm. The UV absorption properties were tested and the results showed that ZnO nano-structures have an extremely strong absorption in wavelength of 300~380 nm. Photoluminescence spectrum measured at room temperature shows a blue emission at 462 nm and a strong, broad red emission at 620 nm attributed to structural defects. A possible growth mechanism for the formation of flower-like ZnO structures was discussed in detail.  

摘要：One-dimensional (1D) nanostructure materials have been extensively studied because of their potential applications in nanoelectronic devices, such as field-effect transistors, single-electron transistors, photodiodes, and chemical sensors. Among these 1D semiconducting nanomaterials, there has been considerable attention focused on low-dimensional ZnO nanostructures on account of its many interesting properties, such as a wide band gap (3.37 eV), a large exciton binding energy (60 meV), excellent chemical and thermal stability, transparency, biocompatibility, and wide electrical conductivity range. ZnO has probably the richest family of nanostructures among all materials, which exhibits the most splendid and abundant configurations of nanostructures. Single crystal ZnO nanorod is of particular interest due to its potential applications in an emerging area of nanotechnology. Up to now, numerous experimental attempts have been reported to fabricate ZnO nanorod materials, such as molecular beam epitaxy (MBE), pulsed laser deposition (PLD), sputtering, electrochemical deposition, vapor phase transport (VPT), chemical vapor deposition (CVD), thermal evaporation and so on. However, these methods usually require expensive equipment and high operation temperature, which are not compatible with organic substrates for applications in flexible and wearable electronics. Compared with the methods mentioned above, the hydrothermal method as a high performance growth technique for ZnO nanorod/nanowire is especially attractive due to its obvious advantages of low-cost, low temperature operation and environmental friendliness. Moreover, this technique can be carried out at low temperatures and large scale on all kinds of substrates, regardless of whether it is crystalline or amorphous. The synthesis and properties of Co-doped ZnO nanomaterials have been reported, most attention was paid to their its magnetic properties, but little report is focused on the optical properties of the nanomaterials.In this paper, Co-doped ZnO nanorod arrays were successfully prepared on quartz substrate by hydrothermal method at temperature of 95 ℃. The crystal structure, morphology, and optical properties were characte-rized with X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) and reflectance analytic approaches, respectively. XRD results illustrated that Co-doped ZnO nanorod arrays with wurtzite structure are grown densely and vertically on the substrates. SEM images showed that the Co-doped ZnO nanorod arrays have smaller diameter than pure ZnO nanorod arrays. The high-intensity near-band edge ultraviolet (UV) emission peak was observed in room temperature photoluminescence (PL) spectra for the ZnO nanorod arrays on all samples, yet the usually observed defect related to deep level emission is very weak, indicating high optical quality ZnO nanorod arrays can be achieved via this low-temperature easy-process chemical approach. Moreover, the small shift in the UV emission indicated that Co²⁺ ions are substituted for Zn²⁺ in ZnO nanorods.  

摘要：Well-aligned ZnO nanowire arrays were synthesized on Chromium (20 nm) coated glass substrates via chemical vapor deposition (CVD) method in a low temperature. The surface morphology and microstructure of products was characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). Well-aligned ZnO nanowire arrays were prepared on glass in SEM images when the reaction temperature of source come up to 1 350 ℃, the substrate temperature maintains about 450~500 ℃, and the argon gas flow rate is 35 sccm. The presence of only (002) diffraction peak in the XRD patterns indicated that ZnO nanowire arrays exhibits c-axis preferred orientation and good crystal quality.  

摘要：One-dimensional (1D) semiconducting nanomaterials have attracted considerable interest for their potential applications in optoelectronic and microelectronic devices. Among thoses 1D semiconducting nanomaterials, ZnO is a wide band gap semiconductor and one of the most functional materials. On account of its many interesting properties, such as superior emission, chemical and thermal stability, transparency, biocompatibility, and wide electrical conductivity range, ZnO has a variety of applications in an emerging area of nanotechnology. Moreover, as a very important one of ZnO nanostructure groups, ZnO nanorods(NRs) have wide applications in nanoelectronics including nanobased light-emitting diodes (LEDs), field effect transistors (FETs), ultraviolet (UV) lasers, and nanogenerators. Until now, there are numerous experimental methods to prepare ZnO NRs involving molecular beam epitaxy (MBE), sputtering, electrochemical deposition, vapor phase transport (VPT), chemical vapor deposition (CVD), and thermal evaporation. However, most of these attempts need some kind of metals to act as a catalyzer. Aurum, zinc, argentine, and aluminium are often used in these methods, which make the prepared ZnO NRs impure. In the cases the metallic impurities have awful influence on the electrical and optical properties of ZnO NRs, an advanced and catalyst-free ZnO growth method needs to be exploited.In this paper, ZnO NRs were successfully synthesized on indium phosphide (InP) (100) substrates by using pulsed laser deposition (PLD) method with catalyst-free. The morphology, crystal structural and optical properties were characterized with scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoluminescence (PL) analytic approaches, respectively. SEM pattern showed the ZnO nanorods were well-oriented. From the XRD scan results, a strong peak was observed at 34.10° attributed to the ZnO (002) face, indicating that the growth direction is well-oriented along c axis. A typical PL spectrum was measured at room temperature, showing a strong free-excition emission at about 379 nm, with full width at half maximum (FWHM) value of 19 nm, no deep level emission was detected, indicating that the ZnO nanorods produced in this experiment are of high optical quality.  

摘要：Fe-doped ZnO nanoballs Zn_1-xFe_xO,(x=0.1) are prepared by microemulsion route. X-ray diffraction (XRD) and transmission electron microscope (TEM) are used to characterize their structure and morphology. Widen absorption spectrum is measured at room temperature. Exciting with 325 nm laser, the photoluminescence includes violet part peaked at 385 nm and widen visible emission peaked at about 625 nm at low excitation power, and the emission intensities and peak positions of these two parts change along with the laser excitation power density. Absorption and photoluminescence properties of the products are both relevant to Fe-doped situation.  

摘要：Bi-molecular bis zinc was synthesized. Its molecular structure was confirmed by single-crystal X-ray diffraction. Single-crystal data are as follow: space group triclinic, P-1; a=0.971 9(2) nm, b=1.124 8(2) nm, c=1.190 2(2) nm; α=73.099(3)°, β=81.498(3)°, γ=76.476(3)°. Zn(5-MeBTZ)₂ has a good thermal stability. The double-layer devices was employed using Zn(5-MeBTZ)₂ as emitter and NPB as hole-transport material, in which Zn(5-MeBTZ)₂ gave rise to unusually large width in electroluminescence (EL) spectrum, covering almost the range of visible light. The broadened EL spectra were demonstrated to be originated from the exciplexes formed at the interface between NPB and Zn(5-MeBTZ)₂. White OLEDs could be expected to be realized by designing of reasonable device structure.  

摘要：Copolymers of 9,9-dioctylfluorene and 2-thienyl-benzothiadiazole were synthesized by Suzuki reaction. The ratio of two monomers was controlled to achieve near white light-emitting with a single polymer. The optimized color coordinates of the copolymers emission (x=0.40, y=0.32). And the copolymers have good thermal stability with thermal decomposition temperature at about 400 ℃; the film prepared through spin-coa-ting shows good morphology.  

摘要：Three new blue phosphorescent iridium complexes containing 2-(difluorophenyl)-4-methylpyridine as the cyclometalated ligands and 2-(pyridyl-2-yl)imidazole as an ancillary ligand have been synthesized and characterized. The complexes have the general structure (P)₂Ir(pym), where P is cyclometalating ligand 2-(2,4-difluorophenyl)-4-methylpyridine(24f₂pmpyH),2-(3,4-difluorophenyl)-4-methylpyridine (34f₂pmpyH) and 2-(3,5-difluorophenyl)-4-methylpyridine (35f₂pmpyH), pym is 2-(pyridyl-2-yl) imida-zole (pymH). Their structures were identified by FTIR, ¹H-NMR, MS and elemental analysis. The absorption, emission, and cyclic voltammetry of the complexes were systematically investigated. By replacing the ancillary ligand pic with pym can finely tune emission of the iridium complexes, showing blue luminescence wavelength peaked at 461, 480, 490 nm at room temperature in CH₂Cl₂. The (46f₂pmpy)₂Ir(pym) shows 5 nm blue shift in comparison with FIrpic in CH₂Cl₂ solution.  

摘要：In the aqueous solution of pH=7.40, both ciprofloxacin (CPFX) and ofloxacin (OFLX) can quench fluorescence of bovine serum albumin (BSA). The fluorescence intensity is obviously gone down when the two drugs coexist. According to this, studies were established on the interaction between CPFX and OFLX by fluorescence spectrum. It was proved that the interaction between the drugs reduces the binding stability of the drug and protein. At the same time, increase of the free drug concentration will increase the effect of the drugs. The result showed that the quenching mechanism of the combination of bovine serum albumin and drugs is a static procedure. The number of binding sites is 1 in several of system. Based on the theory of Frester spectroscopy energy transfer, the binding distance (r＜7.0 nm) between the drugs and BSA was obtained. It belongs to non-radiation energy transfer. Because of the existence of interaction between the drugs, the correlation coefficient and binding distance are increased. Studies by synchronous spectra show the effect of the interaction between the drugs on conformation of BSA. It makes protein molecules extend and hydrophobic nature reduces.  

摘要：Organic solar cells (OSCs) have attracted considerable attention due to their potential for low-cost and large-area solar energy conversion. A lot of work has been undertaken on the electrode buffer layer, which could improve the interface between the electrode and the organic active materials, block exciton to prevent exciton quench at the interface and increase the charge collection, leading to enhanced performance of the OSCs. In this article, the effect of molybdenum oxide (MoO₃) buffer layer on the performance of the OSCs with a heterojunction of CuPc/C₆₀ was investigated. It was found that the OSCs, with a 10 nm thick MoO₃ anode buffer layer, showed a little smaller short current, open voltage and power conversion efficiency compared to the control devices without the MoO₃ anode buffer layer. However, the stability of the devices with a 10 nm thick MoO₃ anode buffer layer is significantly improved: under uninterrupted illumination, the fill factor, open voltage, and power conversion efficiency of the device without MoO₃ buffer layer decreases 45% during 20 minute continuous operating, while the fill factor, open voltage, and power conversion efficiency of the device with a 10 nm MoO₃ anode buffer layer keeps nearly constant, which is attributed to the suppression of the degradation of the interface between ITO and CuPc caused by the uninterrupted illumination, by inducing a MoO₃ buffer layer into the interface.  

摘要：Taking [Zn₄(OH)₂(O₂CCH₃)₆·2H₂O] as solid sources, ZnO thin films were deposited on quartz and gold-plated quartz substrates by SSCVD technique at normal pressure. The structure and morpho-logy of the samples was characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively, while the optical properties were estimated by photoluminescence(PL) spectra. The results showed that the ZnO thin films with Au buffer layer is of high crystallinic qualities and is highly c-axis oriented. The prepared ZnO thin films on gold-plated quartz substrates at 500 ℃ are found to be compact and uniform, with better crystallinic qualities. A strong band edge emission in the PL spectra associated with the free exciton emission is observed at about 400 nm, while other emissions related to specific defects could be negligible compared with the intensive UV emission, which indicated that the ZnO thin films has low concentration of defects and high crystal qualities.  

摘要：As an important candidate material for photoelectric devices such as ultraviolet detector, thin Mg_xZn_1-xO films (MZO) have been recently given extensive attention. Most studies have been focused on changing target compositions to prepare MZO with absorption edge in the solar-blind region (220~280 nm). However, the mix phases of hexagonal ZnO and cubic MgO appear when the Mg concentration increases to certain percentage. For different growing technologies and parameters, different limits of Mg concentration have been reported to keep MZO single hexagonal phase. Besides, the Mg content in the prepared thin films often deviates from the targets according to most studies. In this paper, a series of thin MZO films were prepared with different growing pressure on the Si(111) and quartz substrates by using Mg_0.2Zn_0.8O target and pulsed laser deposition (PLD) method in order to adjust the Mg content in the prepared MZO samples. The crystal structures, micro-morphologies and optical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersion spectra (EDS) and ultraviolet-visible absorption spectra. The EDS results showed that the Mg concentrations in the prepared samples change from 44.5% to 48.5% with the growing pressure from 5.2×10^-4 Pa to 0.3 Pa, much higher than that in the target. But all the thin films still show single hexagonal phase according to the XRD results. We suggested that the increase of Mg content in the thin films is due to the stronger binding force of Mg-O compared to Zn-O in the oxygen-deficient growing environment. The band-gap of the thin films increases from 3.83 eV to 4.05 eV with the increasing Mg content, which can be estimated from the transmittance spectra. Among all the MZO samples, the 48.5% Mg sample has the shortest absorption edge which is close to 300 nm, quite near the solar-blind region. This work would be helpful for the preparation of solar-bind thin MZO films with single phase.