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51.
采用简易的两步水热法在FTO导电玻璃表面合成碘氧铋/二氧化钛纳米棒(BiOI/TiO2 NRAs)复合材料。通过扫描电子显微镜、X射线单晶衍射仪对该复合材料进行了表征,基于电流-时间法考察了其光电化学行为。 BiOI的负载不仅成功地将TiO2的光吸收范围拓展到可见光区,同时二者结合形成的p-n异质结构有效地促进光生电子空穴分离,增强了光催化能力。 基于该复合材料对双酚A的光催化氧化作用,建立了一种新型检测双酚A的方法。 结果表明,420 nm可见光激发下,利用电流-时间法,在外加偏压为0.0 V时,光电流密度与双酚A浓度在0.0047~14.7 μmol/L范围内呈线性关系,检测限为0.93 nmol/L(S/N=3)。 该传感器具有高的灵敏度、良好的稳定性及重现性,将其应用于塑料制品和牛奶中的双酚A检测,获得令人满意的结果,回收率为98.0%~107.1%。 相似文献
52.
Direct evidence of effects of surface plasmon resonance(SPR) of gold nanorods(GNRs) on dual-band light absorption enhancement with coupling dye molecules was reported by introducing gold nanorod@SiO2(GNR@SiO2) core-shell nanoparticles into a photoelectric conversion system. GNR with asymmetric shape had unusual anisotropic SPR[transversal surface plasmon resonance(TSPR) and longitudinal surface plasmon resonance(LSPR)]. The excellent SPR of GNR made it a promising candidate as enhancing light absorption material to increase power conversion efficiency(PCE). The PCE was improved nearly 17.2% upon incorporating GNRs, mostly due to the increase in Jsc, while Voc and FF were unchanged. The improvement was mostly contributed by the SPR of the GNRs with coupling of N719. And there was also a complementary to N719 in visible light range. Therefore, SPR is an effective tool in improving the photocurrent and consequently enhancement of PCE. The TSPR and LSPR effects of GNRs on light harvesting were reflected in the increased monochromatic incident photon-to-electron conversion efficiency(IPCE). We also utilized finite-difference time-domain(FDTD) to investigate the light coupling of GNRs with TiO2. Compare to the base anode, the IPCE of optimized electrode showed significant improvement and peaks broadening at 500-600 nm and 610-710 nm. We got an increase in overall conversion efficiency from 6.4% to 7.5%. 相似文献
53.
Hydrothermally processed highly photosensitive ZnO nanorods based plasmon field effect transistors (PFETs) have been demonstrated utilizing the surface plasmon resonance coupling of Au and Pt nanoparticles at Au/Pt and ZnO interface. A significantly enhanced photocurrent was observed due to the plasmonic effect of the metal nanoparticles (NPs). The Pt coated PFETs showed Ion/Ioff ratio more than 3 × 104 under the dark condition, with field-effect mobility of 26 cm2 V−1 s−1 and threshold voltage of −2.7 V. Moreover, under the illumination of UV light (λ = 350 nm) the PFET revealed photocurrent gain of 105 under off-state (−5 V) of operation. Additionally, the electrical performance of PFETs was investigated in detail on the basis of charge transfer at metal/ZnO interface. The ZnO nanorods growth temperature was preserved at 110 °C which allowed a low temperature, economical and simple method to develop highly photosensitive ZnO nanorods network based PFETs for large scale production. 相似文献
54.
本文系统地比较了三种方式制备的ZnO纳米棒阵列的结构和性能的异同.根据水热法生长液中碱来源的不同,ZnO纳米棒阵列的生长方式分为三种:N方式(氨水)、H方式(六次甲基四胺)和NH方式(两次N方式和一次H方式).通过扫描电子显微镜,对这三种方式生长的ZnO纳米棒阵列形貌进行了表征.此外,利用X射线衍射仪、透射电子显微镜和激光拉曼光谱对ZnO的结晶性能进行比较.结果表明,ZnO纳米棒阵列的取向性N≈NH>H,ZnO的晶体质量H>NH>N.NH方式综合N方式和H方式的优势,得到了取向性和晶体质量优良的ZnO纳米棒阵列.这将为在进一步应用中有效地选择ZnO纳米棒阵列的制备方式提供重要信息. 相似文献
56.
57.
Shaohuan Liu Lixia Yang Shihai Xu Shenglian Luo Qingyun Cai 《Electrochemistry communications》2009,11(9):1748-1751
A C–N-doped TiO2 nanotube (NT)/carbon nanorod composite is fabricated by chemical vapor deposition (CVD). Carbon nanorods are grown from the TiO2 NTs, and partly graphitized, while TiO2 is in the mixture of anatase and rutile. The C–N doping shifts the absorption edge of TiO2 NTs to the visible light region; the formed carbon nanorods promote the charge carrier transfer from the TiO2 surface to the electrolyte. Under the simulated solar light irradiation, the C–N-doped TiO2 NTs show higher photocatalytic activity in the degradation of methyl orange (MO) than the undoped TiO2 NTs. 相似文献
58.
Various TiO2 nanostructures, such as nanorings, nanorods were synthesized via potentiostatic anodization of titanium powder under different conditions. The morphology of the obtained TiO2 nanostructures can be easily tuned by varying applied voltage. The crystal structure, compositional information and morphological structures were characterized by X‐ray diffraction (XRD), X‐ray photoelectron spectra (XPS) and field emission scanning electronic microscopy (FESEM). XRD and XPS analysis confirmed the anodization products were TiO2. A possible formation mechanism was suggested on the basis of the shape evolution of TiO2 nanostructures observed by FESEM. The results revealed that the applied voltage played an important role in the formation of various nanostructures. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
59.
Optical total reflection and transmission with mode control in a dielectric subwavelength nanorod chain
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We report a polarization dependent reflection phenomenon beyond the normal incidence with a subwavelength nanorod chain.Light waves of the transverse electric mode will be totally reflected while those of the transverse magnetic mode will transmit through.The total reflection or transmission phenomenon can be seen as a constructive or destructive interference of the incident field with the transverse mode field of the chain.With the low-loss feature and the ultra-compact characteristic,this structure may find applications in photonic circuits. 相似文献
60.
Surface-field-induced effects on morphologies of lamella-forming diblock copolymers in nanorod arrays
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The surface-induced effect on the morphologies of lamella-forming diblock copolymers in nanorod arrays is studied by using the self-consistent field theory.In the simulation study,a rich variety of novel morphologies are observed by variations in the strength of the surface field for the diblock copolymers.Different surface-field-induced effects are examined for the diblock copolymers in the arrays with distinct preferential surfaces.It is observed that the majority-block preferential surfaces have more obvious induced effects than those of minority-block preferential surfaces.The strong surface fields exhibit different behaviours from those observed in the weak surface fields,by which the morphologies possess cylindrical symmetries.Results from this research deepen the knowledge of surface-induced effects in a confinement system,which may aid the fabrication of polymer-based nanomaterials. 相似文献