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Davide Barreca Giorgio Carraro Alberto Gasparotto Chiara Maccato Cinzia Sada Aadesh P. Singh Sanjay Mathur Andreas Mettenbörger Elza Bontempi Laura E. Depero 《International Journal of Hydrogen Energy》2013
A single-step plasma enhanced-chemical vapor deposition (PE-CVD) route for the synthesis of F-doped iron(III) oxide nanomaterials is presented. Growth experiments, performed from a fluorinated Fe(II) β-diketonate precursor on Indium Tin Oxide (ITO) between 200 and 400 °C, yielded columnar β-Fe2O3 arrays with a preferential (100) growth direction. The fluorine content in the deposits could be adjusted by the sole variation of the deposition temperature controlling, in turn, the optical absorption and energy bandgap. Photocurrent measurements and Mott–Schottky analyses, carried out in Na2SO4 solution under one sun illumination, evidenced a conductivity switch from n- to p-type upon increasing fluorine amount in the obtained nanomaterials. The sample photocurrent density, donor content and flatband potential support the hypothesis that a progressive substitution of oxygen by fluorine in the iron(III) oxide lattice can alter electronic structure and extend charge carrier lifetimes, making anion-doped β-Fe2O3 an efficient water oxidation catalyst. 相似文献
53.
离子选择电极法测定牙膏中氟含量的研究与探讨 总被引:1,自引:0,他引:1
本文对离子选择电极法测定牙膏中氟化物进行了研究与探讨.讨论了仪器精度、共存离子引入的误差及干扰、测定的pH值范围、电极相关因素的影响、搅拌的影响和测定中应注意的问题等因素对氟离子选择电极法测定牙膏中氟化物的影响。该方法具有选择性好,准确、快速、检测范围宽的特点. 相似文献
54.
We have investigated the concentration of fluorine in a newly formed film, which is located on the etched surface during modification of thermal silicon dioxide layer in reactive-ion-etching (RIE) system in CF4 plasma. We try to find the correlation between parameters of the RIE process, depth and concentration of implanted fluorine ions, and finally, the thermal stability of fluorine ions incorporated into etched layer.During the RIE of silicon dioxide in fluorine plasma, on the etched surface a layer containing fluorine atoms is formed. This layer is very thin (about 1.5 nm) and has high concentration of fluorine ions. This concentration can be changed with r.f. power, CF4 gas pressure and CF4 flow. The suitable selection of etching parameters makes inspection of concentration and of the depth of fluorine ions incorporated into silicon possible, during the etching process. Unfortunately, ultra-shallow junction formed in this way does not show resistance to high temperature. So it is recommended only for low-budget technologies. 相似文献
55.
Effect of interfacial fluorination on the electrical properties of the inter-poly high-k dielectrics
Chih-Ren HsiehYung-Yu Chen Kwung-Wen LuGray Lin Jen-Chung Lou 《Microelectronic Engineering》2011,88(6):945-949
In this paper, the reliabilities and insulating characteristics of the fluorinated aluminum oxide (Al2O3) and hafnium oxide (HfO2) inter-poly dielectric (IPD) are studied. Interface fluorine passivation has been demonstrated in terminating dangling bonds and oxygen vacancies, reducing interfacial re-oxidation and smoothing interface roughness, and diminishing trap densities. Compared with the IPDs without fluorine incorporation, the results clearly indicate that fluorine incorporation process is effective to improve the insulating characteristics of both the Al2O3 and HfO2 IPDs. Moreover, fluorine incorporation will also improve the dielectric quality of the interfacial layer. Although HfO2 possesses higher dielectric constant to increase the gate coupling ratio, the results also demonstrate that fluorination of the Al2O3 dielectric is more effective to promote the IPD characteristics than fluorination of the HfO2 dielectric. For future stack-gate flash memory application, the fluorinated Al2O3 IPD undoubtedly possesses higher potential to replace current ONO IPD than the fluorinated HfO2 IPD due to superior insulating properties. 相似文献
56.
Acrylic acid (AAc) and styrene (St) were grafted onto poly(vinylidene fluoride) (PVDF) powder or membrane samples by pre-irradiation graft copolymerization.The grafted chains were proved by FT-IR spectroscopy analysis.The degree of grafting (DG) of the grafted PVDF was determined by fluorine elemental analysis (FEA) method,and was compared with the DGs determined by weighing method,acid-base back titration method and quantitative FT-IR method.The results show that the FEA method is accurate,convenient and universal,especially for the grafted polymer powders. 相似文献
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The fluorine losses during synthesis of Er3+ doped transparent glasses in the SiO2–PbO–PbF2 system were investigated. The final fluorine contents of the glasses were detected by using a fluorine ion selective electrode. The results show that high fluorine losses are occured in the normal preparation processes. With the increase of initial PbF2 contents or melting time resulted in the increase of the fluorine losses. The thermal and spectroscopic properties of the glasses and the corresponding glass ceramics were investigated through the analysis of the differential scanning calorimetry (DSC), absorption and upconversion luminescence spectra. The effects of fluorine contents show a decrease of the glass transition temperatures (Tg) of the glasses and an enhancement of upconversion intensity of the corresponding glass ceramics. 相似文献
60.
Koji Honda Ikuo Yamamoto Masamichi Morita Hiroki Yamaguchi Hiroshi Arita Ryohei Ishige Yuji Higaki Atsushi Takahara 《Polymer》2014
The effect of α-substituent on the molecular motion and wetting behavior of poly{2-(perfluorobutyl)ethyl acrylate} [PFA-C4], poly{2-(perfluorobutyl)ethyl methacrylate} [PFMA-C4], poly{2-(perfluorobutyl)ethyl α-fluoroacrylate} [PFFA-C4], and poly{2-(perfluorobutyl)ethyl α-chloroacrylate} [PFClA-C4] films were characterized by dynamic contact angle measurement, lateral force microscopy (LFM), wide angle X-ray diffraction (WAXD), and X-ray photoelectron spectroscopy (XPS). WAXD of oriented PFClA-C4 fiber suggested the presence of rod-like chain due to the presence of bulky α-substituent. The glass transition temperature (Tg) of PFFA-C4 and PFClA-C4 were well above the room temperature. The water repellencies of PFFA-C4 and PFClA-C4 were as high as that of PFMA-C4 and their oil repellency of PFFA-C4 and PFClA-C4 was higher than the PFMA-C4. This result was originated from the low main chain mobility of PFFA-C4 and PFClA-C4 due to the presence of bulky α-substituents. The effect of molecular motion on water repellency was clarified by the results of temperature dependence studies of dynamic contact angle, LFM, and surface chemical composition measured by XPS. 相似文献