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Single-crystal Eu3+-doped wurtzite ZnO micro- and nanowires were synthesized by chemical vapor deposition. The nanostructures grew via a self-catalytic mechanism on the walls of an alumina boat. The structure and properties of the doped ZnO were characterized using X-ray diffraction, energy-dispersive X-ray spectroscopy, scanning and transmission electron microscopy, and photoluminescence (PL) methods. A 10-min synthesis yielded vertically grown nanowires of 50–400 nm in diameter and several micrometers long. The nanowires grew along the ±[0001] direction. The Eu3+ concentration in the nanowires was 0.8 at.%. The crystal structure and microstructure of were compared for Eu3+-doped and undoped ZnO. PL spectra showed a red shift in emission for Eu3+-doped (2.02 eV) compared to undoped ZnO nanowires (2.37 eV) due to Eu3+ intraionic transitions. Diffuse reflectance spectra revealed widening of the optical bandgap by 0.12 eV for Eu3+-doped compared to undoped ZnO to yield a value of 3.31 eV. Fourier-transform infrared spectra confirmed the presence of europium in the ZnO nanowires. 相似文献
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M. R. Annenkov B. A. Kulnitskiy I. A. Perezhogin D. A. Ovsyannikov M. Yu. Popov V. D. Blank 《Physics of the Solid State》2017,59(5):929-933
Transmission electron microscopy has been used to study the structural features of boron carbide treated in a high-pressure shear chamber with diamond anvils in the pressure range 25–55 GPa. Such a treatment has been shown to lead to the predominant crack formation along planes {10 11 } and {10 12} and also the formation of polytypes in the {10 11} planes and strain bands in the {10 12} planes. 相似文献
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D. A. Ovsyannikov M. Yu. Popov S. A. Perfilov V. M. Prokhorov B. A. Kulnitskiy I. A. Perezhogin V. D. Blank 《Physics of the Solid State》2017,59(2):327-330
A new type of ceramics based on the phases of fullerite derivatives and boron carbide B4C is obtained. The material is synthesized at a temperature of 1500 K and a relatively low pressure of 4 GPa; it has a high hardness of 45 GPa and fracture toughness of 15 MPa m1/2. 相似文献
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S. A. Al Rifai B. A. Kulnitskiy 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(5):1049-1056
Nitrogen-doped (N-doped) self-assembled nanotetrapods ZnO were synthesized via chemical vapor deposition process using N2O as a dopant source via vapor-solid (VS) growth. The decomposition of N2O gas giving NO and NO2 during the synthesis provided successful N-doping of the sample. All samples (N-doped and undoped) were characterized by XRD, SEM, TEM, EDX, photoluminescence (PL), Fourier transform infrared (FT-IR), and diffuse reflection spectra. After nitrogen-doping process, N-doped ZnO samples show the change in structural and optical properties. The detailed structure and the growth mechanism of individual ZnO tetrapod is characterized by TEM and SEM investigations. The TEM study gives the direct assumption about the formation of zincblende (sphalerite) structure on the initial stage of growth of N-doped tetrapods. Besides, SEM observation indicated that tetrapods have perfect tetrahedral symmetry. N-Doped ZnO samples exhibit a broad orange-red PL emission band, peaking near 2.1 eV, in good agreement with the deep-acceptor model for the nitrogen impurity. An IR absorption peak at 3146 cm–1 at room temperature was observed for N-doped sample. This peak has been unambiguously assigned to N–H complex. 相似文献
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V. A. Demin V. D. Blank A. R. Karaeva B. A. Kulnitskiy V. Z. Mordkovich Yu. N. Parkhomenko I. A. Perezhogin M. Yu. Popov E. A. Skryleva S. A. Urvanov L. A. Chernozatonskii 《Journal of Experimental and Theoretical Physics》2016,123(6):985-990
A new fully carbon nanocomposite material is synthesized by the immersion of carbon nanotubes in a fullerene solution in carbon disulfide. The presence of a dense layer of fullerene molecules on the outer nanotube surface is demonstrated by TEM and XPS. Fullerenes are redistributed on the nanotube surface during a long-term action of an electron beam, which points to the existence of a molecular bond between a nanotube and fullerenes. Theoretical calculations show that the formation of a fullerene shell begins with the attachment of one C60 molecule to a defect on the nanotube surface. 相似文献
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Gordeeva T. Kulnitskiy B. Popov M. Ovsyannikov D. Blank V. 《Physics of the Solid State》2021,63(6):844-849
Physics of the Solid State - As a result of high-resolution transmission electron microscopy (HRTEM) studies of silicon processed in a planetary mill in the presence of diamond powder,... 相似文献
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Gordeeva T. A. Ovsyannikov D. A. Popov M. Yu. Kulnitskiy B. A. Blank V. D. 《Physics of the Solid State》2020,62(10):1765-1768
Physics of the Solid State - The structure of a powder germanium treated in a planetary mill in the presence of small (5–25%) additions of diamond powder has been studied by high-resolution... 相似文献
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