Articles de revues : « Doped Nanocrystals »

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Della Gaspera, Enrico, Noel W. Duffy, Joel van Embden, Lynne Waddington, Laure Bourgeois, Jacek J. Jasieniak et Anthony S. R. Chesman. « Plasmonic Ge-doped ZnO nanocrystals ». Chemical Communications 51, n^o 62 (2015) : 12369–72. http://dx.doi.org/10.1039/c5cc02429c.

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Zhang, Xinhai, Qiuling Chen et Shouhua Zhang. « Ta2O5 Nanocrystals Strengthened Mechanical, Magnetic, and Radiation Shielding Properties of Heavy Metal Oxide Glass ». Molecules 26, n^o 15 (26 juillet 2021) : 4494. http://dx.doi.org/10.3390/molecules26154494.

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In this study, for the first time, diamagnetic 5d0 Ta5+ ions and Ta2O5 nanocrystals were utilized to enhance the structural, mechanical, magnetic, and radiation shielding of heavy metal oxide glasses. Transparent Ta2O5 nanocrystal-doped heavy metal oxide glasses were obtained, and the embedded Ta2O5 nanocrystals had sizes ranging from 20 to 30 nm. The structural analysis of the Ta2O5 nanocrystal displays the transformation from hexagonal to orthorhombic Ta2O5. Structures of doped glasses were studied through X-ray diffraction and infrared and Raman spectra, which reveal that Ta2O5 exists in highly doped glass as TaO6 octahedral units, acting as a network modifier. Ta5+ ions strengthened the network connectivity of 1–5% Ta2O5-doped glasses, but Ta5+ acted as a network modifier in a 10% doped sample and changed the frame coordination units of the glass. All Ta2O5-doped glasses exhibited improved Vicker’s hardness, magnetization (9.53 × 10−6 emu/mol), and radiation shielding behaviors (RPE% = 96–98.8%, MAC = 32.012 cm2/g, MFP = 5.02 cm, HVL = 0.0035–3.322 cm, and Zeff = 30.5) due to the increase in density and polarizability of the Ta2O5 nanocrystals.

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Chen, Yi Chuan, Yue Hui Hu, Xiao Hua Zhang, Feng Yang, Hai Jun Xu, Xin Hua Chen et Jun Chen. « Structure and Properties of Doped ZnO Nanopowders Synthesized by Methanol Alcoholysis Method ». Advanced Materials Research 287-290 (juillet 2011) : 1406–11. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.1406.

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Pured ZnO, Al doped ZnO and Al-In co-doped ZnO nanopowders were synthesized by the methanol alcoholysis method at 130 °C. Structure, morphology and optical properties of ZnO nanopowders were characterized using X-ray diffraction, Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and Photoluminescence (PL) spectra. The results show that ZnO nanopowders can be obtained in methanol solution at low temperature (130 °C). TEM images show that Al doped ZnO nanocrystals grow along the [002] axis quicker than other axes. FTIR spectra show that ZnO nanocrystals synthesized by the methanol alcoholysis include a little organic impurity. PL spectrums reveal that pure ZnO and doped ZnO nanocrystals have a blue band emission at 440 nm and a green band emission at 520 nm and 530 nm, respectively. Compared with the pure ZnO nanocrystal, the Al doping improves the luminescent properties.

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Ishigaki, Takamasa, Ji Guang Li et Yusuke Moriyoshi. « Thermal Plasma Processing of Functional Ceramic Materials ». Advances in Science and Technology 45 (octobre 2006) : 281–84. http://dx.doi.org/10.4028/www.scientific.net/ast.45.281.

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Fe- and Eu-doped TiO2 nanocrystals were synthesized via Ar/O2 thermal plasma oxidation of liquid precursor mists. The use of mists ensures atomic level mixing of the elements and high supersaturation of the evaporated species upon plasma oxidation, which favors nanocrystal formation upon condensation. Iron-doped TiO2 nanopowders with controlled iron to titanium atomic ratios (RFe/Ti) ranging from 0 to 20%, were synthesized by oxidative pyrolysis of liquid-feed metallorganic precursors containing titanium tetra-n-butoxide (TTBO) and ferrocene. Europium doped TiO2 luminescent nanocrystals were also synthesized via RF thermal plasma oxidation of liquid precursor mists containing TTBO and europium nitrate.

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Dong, Hehe, Yinggang Chen, Yan Jiao, Qinling Zhou, Yue Cheng, Hui Zhang, Yujie Lu, Shikai Wang, Chunlei Yu et Lili Hu. « Nanocrystalline Yb:YAG-Doped Silica Glass with Good Transmittance and Significant Spectral Performance Enhancements ». Nanomaterials 12, n^o 8 (8 avril 2022) : 1263. http://dx.doi.org/10.3390/nano12081263.

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In this study, Yb:YAG-nanocrystal-doped silica glass with high transmission and excellent spectral properties was successfully prepared using a modified sol–gel method. The X-ray diffraction (XRD), micro-Raman spectroscopy, electron paramagnetic resonance (EPR), transmission electron microscopy (TEM), and high-resolution TEM (HR-TEM) analyses confirmed that the Yb:YAG nanocrystals, with their low content, homogeneous distribution, and small crystal size, directly crystallized into the silica glass network without annealing treatment. In contrast with conventional microcrystalline glass having large particles (>0.1 μm) and a large particle content, nanocrystalline glass with a homogeneous distribution and sizes of ~22 nm had higher optical transmittance and better spectral properties. Compared with Yb3+ doped silica glass without nanocrystals, the Yb:YAG-nanocrystal-doped silica glass had a 28% increase in absorption cross-section at 975 nm and a 172% enhanced emission cross-section at 1030 nm without any changes in the spectral pattern of the Yb3+ ions in the silica glass. Meanwhile, the Yb:YAG-doped silica glass with large size and high optical quality was easily prepared. Therefore, the Yb:YAG-nanocrystal-doped silica glass is expected to be a promising near-infrared laser material.

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Kang, Myung Jong, Na Hyeon An et Young Soo Kang. « Magnetic and Photochemical Properties of Cu Doped Hematite Nanocrystal ». Materials Science Forum 893 (mars 2017) : 136–43. http://dx.doi.org/10.4028/www.scientific.net/msf.893.136.

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In this report, the magnetic and photochemical properties of Cu doped hematite nanocrystal was investigated intensively. The Cu doped hematite nanocrystals were prepared by hydrothermal method, changing the molar ratio of Cu precursors. The XRD and XPS techniques are used for revealing crystal and chemical state of Cu doped hematite nanocrystal. Raman spectroscopy was also used for confirming Cu atoms replacing Fe position in Cu doped hematite crystal. The UV-vis and UPS were used for assigning electronic band position for photocatalytic properties. Cu doped hematite showed the enhanced photocatalytic properties within photodegradation of methyl orange. Finally, by checking magnetic hysteresis loops of Cu doped hematites with VSM, it was revealed that the magnetic property of Cu doped hematite nanocrystal was increased after doping Cu into hematite nanocrystal, get the distortion of magnetic sub-lattices.

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JACOBY, MITCH. « DOPED NANOCRYSTALS ». Chemical & ; Engineering News 83, n^o 28 (11 juillet 2005) : 9. http://dx.doi.org/10.1021/cen-v083n028.p009.

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Norris, D. J., A. L. Efros et S. C. Erwin. « Doped Nanocrystals ». Science 319, n^o 5871 (28 mars 2008) : 1776–79. http://dx.doi.org/10.1126/science.1143802.

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JAVAN, MASOUD BEZI. « ELECTRONIC AND OPTICAL PROPERTIES OF NITROGEN DOPED SiC NANOCRYSTALS : FIRST PRINCIPLES STUDY ». International Journal of Modern Physics B 27, n^o 13 (15 mai 2013) : 1350053. http://dx.doi.org/10.1142/s0217979213500537.

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A typical nitrogen doped spherical SiC nanocrystal with a diameter of 1.2 nm ( Si 43 C 44 H 76) using linear combination atomic orbital (LCAO) in combination with pseudopotential density functional calculation have been studied. Our selected SiC nanocrystal has been modeled taking all the cubic bulk SiC atoms contained within a sphere of a given radius and terminating the surface dangling bonds with hydrogen atoms. We have examined nine possible situations in which nitrogen has a high probability for replacement in the lattice or placed between atoms in the nanocrystal. We have found that the silicone can substitute with a nitrogen atom in each layer as the constructed nanocrystals remain thermodynamically stable. Also the nitrogen atom can be placed between the free atomic spaces as the more thermodynamically stable position of the nitrogen is between the topmost layers. Also the optical absorption and refractive index energy dispersions of the pure and various stable doped SiC nanocrystals were studied.

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Sung, Yun-Mo, Woo-Chul Kwak, Woong Kim et Tae Geun Kim. « Enhanced ripening behavior of Mg-doped CdSe quantum dots ». Journal of Materials Research 23, n^o 7 (juillet 2008) : 1916–21. http://dx.doi.org/10.1557/jmr.2008.0238.

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Pure CdSe and Mg-doped CdSe nanocrystal quantum dots were synthesized into the zinc-blende structure at a low temperature by the inverse micelle technique using paraffin oil and oleic acid as surface capping agents. The ripening behavior of the nanocrystals was monitored using the red shift in ultraviolet (UV)-visible light absorption peaks, and their size variation was estimated using the so-called, quantum confinement theory. The Lifshitz–Slyozov–Wagner (LSW) kinetics analyses were performed based on the variation in size according to the ripening temperature and time period. The activation energy (Q) and reaction rate constant (Ko) were determined for the ripening reaction using Arrhenius-type plots. The kinetics analyses reveal that the volume diffusion through the liquid-phase solution is the governing mechanism for the ripening of both nanocrystals. The Mg-doped CdSe nanocrystals showed enhanced ripening kinetics due to the low activation energy for the volume diffusion.

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Sercel, Peter C., Andrew Shabaev et Alexander L. Efros. « Symmetry Breaking Induced Activation of Nanocrystal Optical Transitions ». MRS Advances 3, n^o 14 (2018) : 711–16. http://dx.doi.org/10.1557/adv.2018.19.

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ABSTRACTWe have analysed the effect of symmetry breaking on the optical properties of semiconductor nanocrystals due to doping by charged impurities. Using doped CdSe nanocrystals as an example, we show the effects of a Coulomb center on the exciton fine-structure and optical selection rules using symmetry theory and then quantify the effect of symmetry breaking on the exciton fine structure, modelling the charged center using a multipole expansion. The model shows that the presence of a Coulomb center breaks the nanocrystal symmetry and affects its optical properties through mixing and shifting of the hole spin and parity sublevels. This symmetry breaking, particularly for positively charged centers, shortens the radiative lifetime of CdSe nanocrystals even at room temperature, in qualitative agreement with the increase in PL efficiency observed in CdSe nanocrystals doped with positive Ag charge centers [A. Sahu et.al., Nano Lett. 12, 2587, (2012)]. The effect of the charged center on the photoluminescence and the absorption spectra is shown, with and without the presence of compensating charges on the nanocrystal surface. While spectra of individual nanocrystals are expected to shift and broaden with the introduction of a charged center, configuration averaging and inhomogeneous broadening are shown to wash out these effects. The presence of compensating charges at the NC surface also serves to stabilize the band edge transition energies relative to NCs with no charge centers.

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Saez Cabezas, Camila A., Gary K. Ong, Ryan B. Jadrich, Beth A. Lindquist, Ankit Agrawal, Thomas M. Truskett et Delia J. Milliron. « Gelation of plasmonic metal oxide nanocrystals by polymer-induced depletion attractions ». Proceedings of the National Academy of Sciences 115, n^o 36 (20 août 2018) : 8925–30. http://dx.doi.org/10.1073/pnas.1806927115.

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Gelation of colloidal nanocrystals emerged as a strategy to preserve inherent nanoscale properties in multiscale architectures. However, available gelation methods to directly form self-supported nanocrystal networks struggle to reliably control nanoscale optical phenomena such as photoluminescence and localized surface plasmon resonance (LSPR) across nanocrystal systems due to processing variabilities. Here, we report on an alternative gelation method based on physical internanocrystal interactions: short-range depletion attractions balanced by long-range electrostatic repulsions. The latter are established by removing the native organic ligands that passivate tin-doped indium oxide (ITO) nanocrystals while the former are introduced by mixing with small PEG chains. As we incorporate increasing concentrations of PEG, we observe a reentrant phase behavior featuring two favorable gelation windows; the first arises from bridging effects while the second is attributed to depletion attractions according to phase behavior predicted by our unified theoretical model. Our assembled nanocrystals remain discrete within the gel network, based on X-ray scattering and high-resolution transmission electron microscopy. The infrared optical response of the gels is reflective of both the nanocrystal building blocks and the network architecture, being characteristic of ITO nanocrystals’ LSPR with coupling interactions between neighboring nanocrystals.

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Żaba, Adam, Svitlana Sovinska, Tetiana Kirish, Adam Węgrzynowicz et Katarzyna Matras-Postołek. « Photodegradation Process of Organic Dyes in the Presence of a Manganese-Doped Zinc Sulfide Nanowire Photocatalyst ». Materials 14, n^o 19 (6 octobre 2021) : 5840. http://dx.doi.org/10.3390/ma14195840.

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Zinc sulfide (ZnS) nanowires represent a promising candidate in many fields, including optoelectronics and photocatalysis because of their advantages such as excellent optical properties, chemical stability and an easy-scalable simple synthesis method. In this study, an energy-friendly microwave radiation process was used to develop the single-step, solvothermal process for the growth of manganese-doped zinc sulfide (ZnS) and undoped nanocrystals (NCs) in the forms of nanowires using two short amines as a stabilizer, e.g. ethylenediamine and hydrazine, respectively. ZnS nanowires doped with Mn atoms show absorbance in UV and in the visible region of the spectrum. The photocatalytic degradation of rhodamine B in the presence of Mn-doped and undoped ZnS nanocrystals illuminated with only a 6-W UV lamp has been comprehensively studied. The effect of Mn doping and the presence of a nanocrystal stabilizer on the degradation process was determined. It was found that the efficiency of a photocatalytic degradation process was strongly affected by both factors: the doping process of nanowires with Mn2+ atoms and the attachment of ligands to the nanocrystal surface.

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Jin, Yizheng, Yuping Ren, MoTao Cao et Zhizhen Ye. « Doped Colloidal ZnO Nanocrystals ». Journal of Nanomaterials 2012 (2012) : 1–8. http://dx.doi.org/10.1155/2012/985326.

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Colloidal ZnO nanocrystals are promising for a wide range of applications due to the combination of unique multifunctional nature and remarkable solution processability. Doping is an effective approach of enhancing the properties of colloidal ZnO nanocrystals in well-controlled manners. In this paper, we analyzed two synthetic strategies for the doped colloidal ZnO nanocrystals, emphasizing our understanding on the critical factors associated with the high temperature and nonaqueous approach. Latest advances of three topics, bandgap engineering, n-type doping, and dilute magnetic semiconductors related to doped ZnO nanocrystals were discussed to reveal the effects of dopants on the properties of the nanocrystalline materials.

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Kasik, I., O. Podrazky, J. Mrazek, J. Cajzl, J. Aubrecht, J. Probostova, P. Peterka, P. Honzatko et A. Dhar. « Erbium and Al2O3 nanocrystals-doped silica optical fibers ». Bulletin of the Polish Academy of Sciences Technical Sciences 62, n^o 4 (1 décembre 2014) : 641–46. http://dx.doi.org/10.2478/bpasts-2014-0070.

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Abstract. Fibre lasers and inherently rare-earth-doped optical fibers nowadays pass through a new period of their progress aiming at high efficiency of systems and their high power. In this paper, we deal with the preparation of silica fibers doped with erbium and Al2O3 nanocrystals and the characterization of their optical properties. The fibers were prepared by the extended Modified Chemical Vapor Deposition (MCVD) method from starting chlorides or oxide nanopowders. Conventional as well as modified approaches led to a nanocrystalline mullite phase formation in the fiber cores in which erbium is dissolved. The proposed modified approach based on starting nanopowders led to improved geometry of preforms and fibers and consequently to the improvement of their background attenuation. Such nanocrystal -doped fibers can be used for ASE sources. Further improvement of fiber optical properties can be expected.

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Clarysse, Jasper, Annina Moser, Olesya Yarema, Vanessa Wood et Maksym Yarema. « Size- and composition-controlled intermetallic nanocrystals via amalgamation seeded growth ». Science Advances 7, n^o 31 (juillet 2021) : eabg1934. http://dx.doi.org/10.1126/sciadv.abg1934.

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Intermetallic nanocrystals are a large family of emerging materials with extensive applications in many fields. Yet, a generalized synthetic method for intermetallic nanocrystals is lacking. Here, we report the development of a colloidal synthesis method based on amalgamation of monometallic nanocrystal seeds with low–melting point metals. We use this approach to achieve crystalline and compositionally uniform intermetallic nanocrystals of Au-Ga, Ag-Ga, Cu-Ga, Ni-Ga, Pd-Ga, Pd-In, and Pd-Zn compounds. We demonstrate both compositional tunability across the phase spaces (e.g., AuGa2, AuGa, Au7Ga2, and Ga-doped Au), size tunability (e.g., 14.0-, 7.6-, and 3.8-nm AuGa2), and size uniformity (e.g., 5.4% size deviations). This approach makes it possible to systematically achieve size- and composition-controlled intermetallic nanocrystals, opening up a multitude of possibilities for these materials.

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Sarkar, Suresh, Amit K. Guria, Biplab K. Patra et Narayan Pradhan. « Synthesis and photo-darkening/photo-brightening of blue emitting doped semiconductor nanocrystals ». Nanoscale 6, n^o 7 (2014) : 3786–90. http://dx.doi.org/10.1039/c3nr06048a.

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Knecht, Tawney A., Shannon W. Boettcher et James E. Hutchison. « Electrochemistry-Induced Restructuring of Tin-Doped Indium Oxide Nanocrystal Films of Relevance to CO₂ Reduction ». Journal of The Electrochemical Society 168, n^o 12 (1 décembre 2021) : 126521. http://dx.doi.org/10.1149/1945-7111/ac40ca.

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The electrochemical reduction of CO2 into fuels using renewable electricity presents an opportunity to utilize captured CO2. Electrocatalyst development has been a primary focus of research in this area. This is especially true at the nanoscale, where researchers have focused on understanding nanostructure-property relationships. However, electrocatalyst structure may evolve during operation. Indium- and tin-based oxides have been widely studied as electrocatalysts for CO2 reduction to formate, but evolution of these catalysts during operation is not well-characterized. Here, we report the evolution of nanoscale structure of precise tin-doped indium oxide nanocrystals under CO2 reduction conditions. We show that sparse monolayer nanocrystal films desorb from the electrode upon charging, but thicker nanocrystal films remain, likely due to an increased number of physical contacts. Upon applying a cathodic voltage of −1.0 V vs RHE or greater, the original 10-nm diameter nanocrystals are no longer visible, and instead form a larger microstructural network. Elemental analysis suggests the network is an oxygen-deficient indium-tin metal alloy. We hypothesize that this morphological evolution is the result of nanocrystal sintering due to oxide reduction. These data provide insights into the morphological evolution of tin-doped indium oxide nanocrystal electrocatalysts under reducing conditions and highlight the importance of post-electrochemical structural characterization of electrocatalysts.

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Jana, Santanu, Bhupendra B. Srivastava, Somnath Jana, Riya Bose et Narayan Pradhan. « Multifunctional Doped Semiconductor Nanocrystals ». Journal of Physical Chemistry Letters 3, n^o 18 (29 août 2012) : 2535–40. http://dx.doi.org/10.1021/jz3010877.

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Kadam, Pratibha, Chitra Agashe et Shailaja Mahamuni. « Al-doped ZnO nanocrystals ». Journal of Applied Physics 104, n^o 10 (15 novembre 2008) : 103501. http://dx.doi.org/10.1063/1.3020527.

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Clavel, Guylhaine, Marc-Georg Willinger, David Zitoun et Nicola Pinna. « Manganese-Doped Zirconia Nanocrystals ». European Journal of Inorganic Chemistry 2008, n^o 6 (février 2008) : 863–68. http://dx.doi.org/10.1002/ejic.200700977.

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Xu, Lili, Man Wang, Qing Chen, Jiajia Yang, Wubin Zheng, Guanglei Lv, Zewei Quan et Chunxia Li. « Rare Earth Hydroxide as a Precursor for Controlled Fabrication of Uniform β-NaYF4 Nanoparticles : A Novel, Low Cost, and Facile Method ». Molecules 24, n^o 2 (19 janvier 2019) : 357. http://dx.doi.org/10.3390/molecules24020357.

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In recent years, rare earth doped upconversion nanocrystals have been widely used in different fields owing to their unique merits. Although rare earth chlorides and trifluoroacetates are commonly used precursors for the synthesis of nanocrystals, they have certain disadvantages. For example, rare earth chlorides are expensive and rare earth trifluoroacetates produce toxic gases during the reaction. To overcome these drawbacks, we use the less expensive rare earth hydroxide as a precursor to synthesize β-NaYF4 nanoparticles with multiform shapes and sizes. Small-sized nanocrystals (15 nm) can be obtained by precisely controlling the synthesis conditions. Compared with the previous methods, the current method is more facile and has lower cost. In addition, the defects of the nanocrystal surface are reduced through constructing core–shell structures, resulting in enhanced upconversion luminescence intensity.

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Qiang, Liang Sheng, Dong Yan Tang, Xing Hong Zhang et L. Jin. « High-Speed Synthesis and Electric Properties of Magnesium Doped Lead Titanate Ceramics ». Solid State Phenomena 121-123 (mars 2007) : 149–52. http://dx.doi.org/10.4028/www.scientific.net/ssp.121-123.149.

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By adding methyl alcohol/water solution with certain concentration into sol to hydrolysis directly and sintering the fresh sol directly, lead titanate(PbTiO3) ceramics doped with magnesium are prepared by using magnesium acetate as doper to prohibit the disadvantages contained in conventional sol-gel method, such as low hydrolytic rate, high sintering temperature, long preparation period. The changes of structure, microstructure, synthesis process and electric properties of modified ceramics are studied in detail. The sizes and morphology of high purely and high density magnesium doped lead titanate nanocrystals thus obtained are observed by TEM photographs and the structures and affection of sintering temperature of to lattice constant and sizes of nanocrystals are detected by XRD. Electric properties detection results show that doped lead titanate ceramics exhibite excellent dielectric, ferroelectric and pyroelectric properties compare with pure lead titanate.

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Dong, Cong. « The Silver Ion and Nanocrystalline Pattern in the Glass Substrate, the Electric Field-Induced Thermal Transfer and Ink Absorption Layer Structure and Printing Performance ». Advances in Materials Science and Engineering 2022 (11 août 2022) : 1–10. http://dx.doi.org/10.1155/2022/4272294.

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People’s research on nanocrystals is getting more in-depth with the development of science and technology, and the patterned arrangement of nanocrystals can greatly improve the performance of our equipment in related fields, allowing people to control the patterning of nanocrystals. Research on thermal transfer is also increasing. Glass materials doped with patterned metal nanocrystals have great application potential, and the search for a simple and efficient patterned preparation method has attracted great attention of many researchers. Using the directional induced migration effect of the high temperature and high voltage DC electric field, combined with the subsequent heat treatment process, the distribution of silver nanocrystals corresponding to the surface silver film pattern can be formed in the silicate glass substrate, to realize the electric field-induced thermal transfer of the nanocrystal pattern print. This article aims to study the patterned thermal transfer of silver ions and nanocrystals on the glass substrate by applying an electric field to induce and analyze the ink absorption layer structure and printing performance. On this basis, an electron beam-induced thermal transfer method and Maxwell’s equation are proposed to investigate and calculate the structure of the ink absorption layer. The experimental structure shows that using this method increases the success rate of the preparation of silver ions and nanocrystal patterns on the glass substrate by 30%, which improves the ink absorption layer and printing performance to different degrees.

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Mote, Vishwanath D., et Babasaheb N. Dole. « Effect of PEG on Structural and Magnetic Properties of Mn Doped ZnO Nanocrystals ». Advanced Materials Research 678 (mars 2013) : 234–38. http://dx.doi.org/10.4028/www.scientific.net/amr.678.234.

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Nanosized Mn doped ZnO samples were synthesized by co-precipitation method using Polyethylene glycol (PEG) as a capping agent. X- ray diffraction patterns confirm that the pure and Mn doped ZnO nanocrystals have wurtzite structure without any seconadary phases. Lattice parameters of pure and Mn doped ZnO nanocrystals increase slightly with increasing Mn concentration. The average crystalline size of pure and Mn doped ZnO nanocrystals are in the range of 14-18 nm. The X-ray density for pure and Mn doped ZnO sample is calculated using lattice parameters. It is found that almost static for Mn doped ZnO samples. In the Zn1-xMnx samples, room temperature magnetic hysteresis is observed and the saturation magnetization increases with increasing Mn content. However, these samples show room temperature ferromagnetic in nature. Result of the present investigation compared without PEG.

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Secu, Corina, Arpad-Mihai Rostas et Mihail Secu. « Europium (II)-Doped CaF2 Nanocrystals in Sol-Gel Derived Glass-Ceramic : Luminescence and EPR Spectroscopy Investigations ». Nanomaterials 12, n^o 17 (31 août 2022) : 3016. http://dx.doi.org/10.3390/nano12173016.

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The remarkable properties of Eu2+-activated phosphors, related to the broad and intense luminescence of Eu2+ ions, showed a high potential for a wide range of optical-related applications. Oxy-fluoride glass-ceramic containing Europium (II)-doped CaF2 nanocrystals embedded in silica matrix were produced in two steps: glass-ceramization in air at 800° with Eu3+-doped CaF2 nanocrystals embedded followed by Eu3+ to Eu2+ reduction during annealing in reducing atmosphere. The broad, blue luminescence band at 425 nm and with the long, weak tail in the visible range is assigned to the d → f type transition of the Eu2+ located inside the CaF2 nanocrystals in substitutional and perturbed sites, respectively; the photoluminescence quantum yield was about 0.76. The X-ray photoelectron spectroscopy and Electron paramagnetic spectroscopy confirmed the presence of Eu2+ inside the CaF2 nanocrystals. Thermoluminescence curves recorded after X-ray irradiation of un-doped and Eu2+-doped glass-ceramics showed a single dominant glow peak at 85 °C related to the recombination between F centers and Eu2+ related hole within the CaF2 nanocrystals. The applicability of the procedure can be tested to obtain an oxy-fluoride glass-ceramic doped with other divalent ions such as Sm2+, Yb2+, as nanophosphors for radiation detector or photonics-related applications.

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Santos, D. A. A., A. D. P. Rocha et M. A. Macêdo. « Rietveld refinement of transition metal doped ZnO ». Powder Diffraction 23, S1 (mars 2008) : S36—S41. http://dx.doi.org/10.1154/1.2903739.

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Nanocrystals of Zn1−xMxO (M=Mn, Co, or Ni) were grown using proteic sol-gel process, and the crystalline phases were identified by X-ray diffraction and Rietveld refinement. The nanocrystals have hexagonal wurtzite structure, with space group P63mc. The insertion of Mn2+ in the place of Zn2+ provoked an increase in the size of the nanocrystals, and the insertion of Co2+ or Ni2+ caused a reduction in the sizes of the nanocrystals, as compared to pure ZnO. This occurred because these three transition metals have very different ionic radii (Co2+=0.58 A˚, Mn2+=0.66 A˚, Ni2+=0.55 A˚, and Zn2+=0.60 A˚).

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Pankratov, V., Larisa Grigorjeva, Donats Millers, Tadeusz Chudoba, Robert Fedyk et Witold Łojkowski. « Time-Resolved Luminescence Characteristics of Cerium Doped YAG Nanocrystals ». Solid State Phenomena 128 (octobre 2007) : 173–78. http://dx.doi.org/10.4028/www.scientific.net/ssp.128.173.

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Time-resolved luminescence characteristics have been studied for cerium doped YAG nanopowders (NP) and nanostructured ceramics (NC). The results obtained have been compared to the luminescence characteristics for the well studied YAG:Ce3+ single crystal (SC). It was detected that the luminescence decay kinetics of Ce3+ related emission in nanocrystals can be closely approximated by two exponents, whereas a single exponential decay was observed in the single crystal. It was also found that the luminescence decay time and light yield of Ce3+ emission are strongly dependent on the cerium concentration and an unusual concentration quenching of Ce3+ emission was observed in YAG nanocrystals. The origin of the differences of luminescence characteristics for cerium doped nanocrystals and SC are discussed. It is suggested that there are special Ce3+ sites which are closely related to the surface states and that they have a strong influence on the luminescence properties of cerium doped YAG nanocrystals.

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Zeng, Ruosheng, Zhiguo Sun, Sheng Cao, Rongan Shen, Zuoji Liu, Ying Xiong, Jingtao Long et al. « Facile synthesis of Ag-doped ZnCdS nanocrystals and transformation into Ag-doped ZnCdSSe nanocrystals with Se treatment ». RSC Advances 5, n^o 2 (2015) : 1083–90. http://dx.doi.org/10.1039/c4ra11064a.

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High-quality, pure, and color-tunable Ag:ZnCdS nanocrystals are prepared by optimization of the experimental conditions, and they can be further transformed into Ag:ZnCdSSe nanocrystals with Se treatment.

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Zhao, Pengcheng, Meiling Zhang, Tianjiao Wang, Xinyang Liu, Xuesong Zhai, Guanshi Qin, Weiping Qin, Fei Wang et Daming Zhang. « Optical Amplification at 1525 nm in BaYF5 : 20% Yb3+, 2% Er3+Nanocrystals Doped SU-8 Polymer Waveguide ». Journal of Nanomaterials 2014 (2014) : 1–6. http://dx.doi.org/10.1155/2014/153028.

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We demonstrated optical amplification in BaYF5: 20% Yb3+, 2% Er3+(BYF) nanocrystals doped polymer waveguide. BYF nanocrystals with an average size of ∼13 nm were synthesized by a high-boiling solvent process. Intense 1.53 μm fluorescence was obtained in the nanocrystals under excitation at 980 nm. An optical polymer waveguide was fabricated by using BYF nanocrystals doped SU-8 polymer as the core material. A relative optical gain of ∼10.4 dB at 1525 nm was achieved in a 1.1 cm long waveguide for an input signal power of ∼0.09 mW and a pump power of ∼212 mW.

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Craievich, A. F., O. L. Alves et L. C. Barbosa. « Formation and Growth of Semiconductor PbTe Nanocrystals in a Borosilicate Glass Matrix ». Journal of Applied Crystallography 30, n^o 5 (1 octobre 1997) : 623–27. http://dx.doi.org/10.1107/s0021889897001799.

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Pb- and Te-doped borosilicate glasses are transformed by appropriate heat treatment into a composite material consisting of a vitreous matrix in which semiconductor PbTe nanocrystals are embedded. This composite exhibits interesting non-linear optical properties in the infrared region, in the range 10–20 000 Å. The shape and size distribution of the nanocrystals and the kinetics of their growth were studied by small-angle X-ray scattering (SAXS) during in situ isothermal treatment at 923 K. The experimental results indicate that nanocrystals are nearly spherical and have an average radius increasing from 16 to 33 Å after 2 h at 923 K, the relative size dispersion being time-invariant and approximately equal to 8%. This investigation demonstrates that the kinetics of nanocrystal growth are governed by the classic mechanism of atomic diffusion. The radius of nanocrystals, deduced by applying the simple Efros & Efros [Sov. Phys. Semicond. (1982), 16, 772–775] model using the energy values corresponding to the exciton peaks of optical absorption spectra, does not agree with the average radius determined by SAXS.

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Farha, Ashraf H., Mervat M. Ibrahim et Shehab A. Mansour. « Ga-Doped ZnO Nanostructured Powder for Cool-Nanopigment in Environment Applications ». Materials 13, n^o 22 (16 novembre 2020) : 5152. http://dx.doi.org/10.3390/ma13225152.

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Gallium (Ga) doped zinc oxide (ZnO) nanocrystals were successfully synthesized via a γ-radiation-assisted polymer-pyrolysis route. Ga doped ZnO samples with Ga and ZnO precursor salts with molar ratios of 0%, 3%, 5%, and 10% were produced. A γ-radiation dosage of 1.5 kGy was used for polymerization initiation during the sample preparation. The properties of the obtained nanocrystal samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), UV-visible absorption, NIR-VIS-UV diffused reflectance, and high-resolution transmission electron microscopy (HR-TEM) characterization techniques. XRD results revealed the formation of ZnO nanocrystals with wurtzite structure for both Ga-doped and undoped ZnO samples. Noticeable increasing in the line broadening of the XRD peaks as well as pronounced decreasing of crystallite size were observed with the increasing Ga ratio in the samples. Optical peaks around Ga:ZnO samples showed a blueshift in the optical absorption peaks with increasing Ga content. These results are in good agreement with the dependency of crystallites size as well as grain size on Ga ratio obtained from XRD and TEM images, which make them fit well for the powder cool-pigment applications. The doped samples showed high values of NIR reflectance (RNIR*) with percentage varied from 84.25% to 89.05% that enabled them to qualify for cool-nanopigment applications. Furthermore, such doped samples registered low values of visible reflectance (RVIS*) that enabled to reduce the glare from the reflected visible sunlight.

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Buonsanti, Raffaella, et Delia J. Milliron. « Chemistry of Doped Colloidal Nanocrystals ». Chemistry of Materials 25, n^o 8 (19 mars 2013) : 1305–17. http://dx.doi.org/10.1021/cm304104m.

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Xiang, Weidong, Shanshan Tang, Xiyan Zhang et Xiaojuan Liang. « Glasses doped with PbS nanocrystals ». Journal of Alloys and Compounds 471, n^o 1-2 (mars 2009) : 498–501. http://dx.doi.org/10.1016/j.jallcom.2008.04.026.

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Zhai, Bao-Gai, Long Yang, Qing-Lan Ma et Yuan Ming Huang. « Visible light driven photocatalytic activity of Fe-doped ZnO nanocrystals ». Functional Materials Letters 10, n^o 02 (avril 2017) : 1750002. http://dx.doi.org/10.1142/s1793604717500023.

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Fe-doped ZnO nanocrystals at the level of 8[Formula: see text]mol% were synthesized via the co-precipitation method and then characterized by transmission electron microscopy, X-ray diffraction, diffuse reflectance spectroscopy and UV–Vis absorption spectroscopy. Strong absorptions with its peak at around 500[Formula: see text]nm were recorded in the range of 400–600[Formula: see text]nm for Fe-doped ZnO nanocrystals. Visible-light driven photocatalytic activity of Fe-doped ZnO nanocrystals was demonstrated via the photocatalytic degradation of methyl orange dye. Density functional calculations show that Fe dopant can generate a deep trap level at Ev [Formula: see text] 1.01[Formula: see text]eV in the bandgap of ZnO, which is believed to be responsible for the visible light responsive photocatalytic activity of Fe-doped ZnO.

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Gedara, Sriyani Menike Korale, Zi-You Ding, Iresha Lakmali Balasooriya, Yingchao Han et Merita Nirmali Wickramaratne. « Hydrothermal Synthesis and In Vivo Fluorescent Bioimaging Application of Eu3+/Gd3+ Co-Doped Fluoroapatite Nanocrystals ». Journal of Functional Biomaterials 13, n^o 3 (29 juillet 2022) : 108. http://dx.doi.org/10.3390/jfb13030108.

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In this study, Eu3+/Gd3+ co-doped fluoroapatitååe (Eu/Gd:FAP) nanocrystals were synthesized by the hydrothermal method as a fluorescent bioimaging agent. The phase composition, morphology, fluorescence, and biosafety of the resulting samples were characterized. Moreover, the in vivo fluorescent bioimaging application of Eu/Gd:FAP nanocrystals was evaluated in mice with subcutaneously transplanted tumors. The results showed that the Eu/Gd:FAP nanocrystals were short rod-like particles with a size of 59.27 ± 13.34 nm × 18.69 ± 3.32 nm. With an increasing F substitution content, the Eu/Gd:FAP nanocrystals displayed a decreased size and enhanced fluorescence emission. Eu/Gd:FAP nanocrystals did not show hemolysis and cytotoxicity, indicating good biocompatibility. In vivo fluorescent bioimaging study demonstrated that Eu/Gd:FAP nanocrystals could be used as a bioimaging agent and displayed stable fluorescence emitting in tumors, indicating an accumulation in tumor tissue due to the passive targeting ability. In addition, any adverse effects of Eu/Gd:FAP nanocrystals on major organs were not observed. This study shows that biocompatible rare earth co-doped FAP nanocrystals have the potential to be used as a bioimaging agent in vivo.

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Callone, Emanuela, Giovanni Carturan, Yoann Jestin et Maurizio Ferrari. « Synthesis Improvement of Yb³⁺-Activated SnO₂ Nanocrystals ». Solid State Phenomena 128 (octobre 2007) : 31–40. http://dx.doi.org/10.4028/www.scientific.net/ssp.128.31.

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Yb3+ doped SnO2 nanocrystals were synthesized, using the hydrolytic route in the presence of starch as the size stabilizer. Starting from salt precursors, the nanopowders obtained with various Yb3+ loads are thermally stable up to 600 °C. They were characterized by XRD, solid state NMR, TEM, ICP and TG-MS techniques. The nanocrystal Cassiterite structure, with a size of a few nanometers (<6 nm), was identified by XRD, NMR and Raman measurements confirming a homogeneous dispersion of Yb3+ ions in the lattice. The preliminary assessment of the spectroscopic features of nanocrystals was performed by absorption and photoluminescence spectroscopy. The typical Yb3+ absorption peak, centred at 977 nm, and an intense 2F5/2→ 2F7/2 Yb3+ emission band were observed.

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Takezawa, Yoko, Minoru Ryu, Yoshiki Iwazaki, Toshimasa Suzuki, Youichi Mizuno et Hiroaki Imai. « Effect of a Boron Additive on the Microstructure and Dielectric Properties of BaTiO₃ Thin Films Formed by Nanocrystal Deposition ». Key Engineering Materials 566 (juillet 2013) : 277–80. http://dx.doi.org/10.4028/www.scientific.net/kem.566.277.

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Highly crystallized BaTiO3 thin films were fabricated by a nanocrystal sintering process. Boron alkoxide was introduced into a slurry of Mn-doped BaTiO3 nanocrystals with particle sizes of 5-7 nm. The deposited nanocrystal film on a (111)-oriented Pt/TiO2/Al2O3 substrate was sintered at a low temperature of 800 °C and the obtained film had highly densified and oriented microstructures. We found that the boron additive enhanced the grain growth of nanoparticles and as a result the dielectric constant of the thin film increased to 1100 at 10 kHz, which is much higher than that of undoped BaTiO3 thin films.

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Ma, Long, Zhiqiang Wei, Xueliang Zhu, Jiahao Liang et Xudong Zhang. « Synthesis and Photocatalytic Properties of Co-Doped Zn1-xCoxMn2O Hollow Nanospheres ». Journal of Nanomaterials 2019 (9 mai 2019) : 1–9. http://dx.doi.org/10.1155/2019/4257270.

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A series of Co-doped Zn1-xCoxMn2O nanocrystals with a spinel structure were successfully prepared by hydrothermal method, and the influence of Co doping concentration on the microstructure, morphology, elemental composition, and optical and photocatalytic properties of the samples was characterized. The experimental results show that all samples exhibit a tetragonal structure, Co2+ ions are successfully substituted for the lattice site of Zn2+ to generate ZnMn2O4 nanocrystals, and the crystalline size decreases as Co-doped concentration increase. The morphologies are loose hollow microsphere structures. The band gap of Zn1−xCoxMn2O samples is smaller than that of pure ZnMn2O4 and has been red shifted. The photocatalytic activity of doped Zn1−xCoxMn2O4 samples is obviously higher than that of pure ZnMn2O4 samples for the photodegradation of MO under visible light irradiation. All these results demonstrate that Co-doped spinel ZnMn2O4 nanocrystals are a meaningful choice for photocatalytic degradation of the pollutants.

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Kendall, Owen, Pierce Wainer, Steven Barrow, Joel van Embden et Enrico Della Gaspera. « Fluorine-Doped Tin Oxide Colloidal Nanocrystals ». Nanomaterials 10, n^o 5 (30 avril 2020) : 863. http://dx.doi.org/10.3390/nano10050863.

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Fluorine-doped tin oxide (FTO) is one of the most studied and established materials for transparent electrode applications. However, the syntheses for FTO nanocrystals are currently very limited, especially for stable and well-dispersed colloids. Here, we present the synthesis and detailed characterization of FTO nanocrystals using a colloidal heat-up reaction. High-quality SnO2 quantum dots are synthesized with a tuneable fluorine amount up to ~10% atomic, and their structural, morphological and optical properties are fully characterized. These colloids show composition-dependent optical properties, including the rise of a dopant-induced surface plasmon resonance in the near infrared.

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Ramrakhiani, Meera, Nitendra Kumar Gautam, Kamal Kushwaha, Sakshi Sahare et Pranav Singh. « Electroluminescence in Chalcogenide Nanocrystals and Nanocomposites ». Defect and Diffusion Forum 357 (juillet 2014) : 127–69. http://dx.doi.org/10.4028/www.scientific.net/ddf.357.127.

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Several research groups have reported that nanocrystalline II-VI semiconductors show enhanced luminescence, increased oscillator strength and shorter response time. Nanocrystalline powder samples of CdS, CdSe, ZnS and ZnSe nanocrystals and their composites with PVA and PVK have been prepared by chemical route. SEM. TEM and AFM images indicate agglomeration of particles. XRD reveal the crystal structure and size in nanometer range and absorption spectra show increased band gap due to quantum confinement.The EL studies on nanocrystalline powder samples and nanocrystal/polymer composites have shown that the light emission starts at certain threshold voltage, different for different specimens and then increases with increasing voltage. It is found that smaller nanocrystals have lower threshold voltage and higher EL brightness. It is observed that nanocomposite give much higher electroluminescence starting at lower voltage and increasing very fast with the voltage as compared to nanocrystalline powder. The emission spectra are found to depend on the material, crystalline size and doping. Electroluminescence in undoped and doped chalcogenide nanocrystals and nanocomposites is reviewed in this paper. In nanosize regime, electroluminescence (EL) is governed by the size quantization effect. Contents of Paper

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Gouget, Guillaume, Morgane Pellerin, Lauriane Pautrot-D'Alençon, Thierry Le Mercier et Christopher B. Murray. « Efficient photoluminescence of isotropic rare-earth oxychloride nanocrystals from a solvothermal route ». Chemical Communications 56, n^o 23 (2020) : 3429–32. http://dx.doi.org/10.1039/d0cc00113a.

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Sub-10 nm near-spherical LaOCl nanocrystals were prepared by solvothermal synthesis from hydrated rare-earth chlorides. Eu³⁺-doped (5%) LaOCl nanocrystals display 43% photoluminescence quantum yield.

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Liang, Zhanguo, Jun Mu, Lei Han et Hongquan Yu. « Microbe-Assisted Synthesis and Luminescence Properties of Monodispersed Tb3+-Doped ZnS Nanocrystals ». Journal of Nanomaterials 2015 (2015) : 1–6. http://dx.doi.org/10.1155/2015/519303.

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Tb3+-doped zinc sulfide (ZnS:Tb3+) nanocrystals were synthesized by spray precipitation with sulfate-reducing bacterial (SRB) culture at room temperature. The morphology of the SRB and ZnS:Tb3+nanocrystals was examined by scanning electron microscopy, and the ZnS:Tb3+nanocrystals were characterized by X-ray diffractometry and photoluminescence (PL) spectroscopy. The PL mechanism of ZnS:Tb3+nanocrystals was further analyzed, and the effects of Tb3+ion concentration on the luminescence properties of ZnS:Tb3+nanocrystals were studied. ZnS:Tb3+nanocrystals showed a sphalerite phase, and the prepared ZnS:Tb3+nanocrystals had high luminescence intensity under excitation at 369 nm. The main peak position of the absorption spectra positively blueshifted with increasing concentrations of Tb3+dopant. Based on the strength of the peak of the excitation and emission spectra, we inferred that the optimum concentration of the Tb3+dopant is 5 mol%. Four main emission peaks were obtained under excitation at 369 nm:489 nm (5D4→7F6), 545 nm (5D4→7F5), 594 nm (5D4→7F4), and 625 nm (5D4→7F3). Our findings suggest that nanocrystals have potential applications in photoelectronic devices and biomarkers.

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Thien, Nguyen Duy, Nguyen Ngoc Tu, Ngo Nhu Viet, Nguyen Duy Phuong, Le Van Vu et Nguyen Ngoc Long. « Hydrothermal Synthesis and Optical Properties of Undoped and \(\text{Eu}^{3+}\)-doped Zinc Stannate Nanocrystals ». Communications in Physics 25, n^o 4 (12 janvier 2016) : 327. http://dx.doi.org/10.15625/0868-3166/25/4/7337.

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Abstract. In this work we report a hydrothermal approach for synthesis of zinc stannate (Zn2SnO4)nanocrystals. Our research focused on the effect of the molar ratio of initial chemicals, reaction temperature and reaction duration on the phase composition and the fluorescence properties.Structural and optical properties of the final products were investigated in detail. X-ray diffractionanalysis indicated that the Zn2SnO4 nanocrystals possess face-centered cubic crystal structure.Raman scattering spectra exhibit two characteristic vibrational modes of Zn2SnO4 crystals. Optical band gap of Eu3+-doped Zn2SnO4 nanocrystals obviously depends on Eu3+content. Theroom-temperature emission spectra of the undoped Zn2SnO4 nanocrystals show two broad bands,while the photoluminescence spectra of Eu3+-doped Zn2SnO4 nanocrystals exhibit the emissionpeaks related to the radiative intra-configurational f-f tr ansitions of Eu3+ions. The absorptiontransitions within Eu3+ions were observed both in the photoluminescence excitation spectra andin the diffuse reflection spectra.

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Barman, Barun Kumar, Bidushi Sarkar et Karuna Kar Nanda. « Pd-coated Ru nanocrystals supported on N-doped graphene as HER and ORR electrocatalysts ». Chemical Communications 55, n^o 92 (2019) : 13928–31. http://dx.doi.org/10.1039/c9cc06208d.

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Pd-coated Ru nanocrystals supported on N-doped graphene (Pd–Ru@NG) are obtained via electroless deposition of Pd on Ru nanocrystals which shows efficient bifunctional HER and ORR electrocatalytic activity.

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Shaoye Ouyang, Shaoye Ouyang, Weihuan Zhang Weihuan Zhang, Zhixiong Zhang Zhixiong Zhang, Yuepin Zhang Yuepin Zhang et Haiping Xia Haiping Xia. « Near-white light-emitting Dy3+-doped transparent glass ceramics containing Ba2LaF7 nanocrystals ». Chinese Optics Letters 13, n^o 9 (2015) : 091601–91604. http://dx.doi.org/10.3788/col201513.091601.

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Li, Renfu, Xiaodie Fang, Jilou Ren, Baojun Chen, Xiaoyun Yuan, Xuechun Pan, Peng Zhang et al. « The effect of surface-capping oleic acid on the optical properties of lanthanide-doped nanocrystals ». Nanoscale 13, n^o 29 (2021) : 12494–504. http://dx.doi.org/10.1039/d0nr08488c.

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The presence of OA on the surface exerted an effect on the optical properties of lanthanide-doped nanocrystals, but a dissimilar variation was observed for nanocrystals in solid state or colloidal solution.

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Xu, Xu Yao, Lin Ma et Xiao Ping Zhou. « Rapid Microwave Synthesis and Fluorescence of LaF₃ and LaF₃:Re (Re=Ce³⁺, Eu³⁺, Tb³⁺) Nanocrystals ». Advanced Materials Research 557-559 (juillet 2012) : 1547–51. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.1547.

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LaF3 and LaF3: Re (Re= Ce3+, Eu3+ and Tb3+) nanocrystals have been successfully synthesized by a facile and rapid microwave heating method. The structure, morphology and fluorescent properties of the as-prepared products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and photoluminescence spectroscopy (PL). XRD patterns showed that the undoped and doped LaF3 nanocrystals had hexagonal structure with good crystallinity and high purity. TEM and HRTEM images showed that the LaF3 nanocrystals have uniform sizes with mean diameter about 20 nm and are characteristic of inner cavities. The luminescence spectra of the LaF3: Re (Re= Ce3+, Eu3+ and Tb3+) nanocrystals indicated that different rare-earth ions have been successfully doped in LaF3 matrix via the microwave heating method.

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Wang, Liyong, Zhenghao Wang, Zhiwen Wang, Chunyang Zhang, Yongling Wu et Hongyu Zheng. « Enhancement of antibacterial function by incorporation of silver-doped ZnO nanocrystals onto a laser-induced graphene surface ». RSC Advances 11, n^o 54 (2021) : 33883–89. http://dx.doi.org/10.1039/d1ra06390a.

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Ag-doped ZnO nanocrystals are incorporated into LIG for enhancing the antibacterial effect. The formulated nanocrystals act as an effective and biocompatible antibacterial agent and yet have a much reduced and acceptable level of Ag concentration.

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Ma, Yunfei, Wenhui Yue, Ziwei Ye et Jinglong Zhang. « Synthesis of nitrogen and terbium co-doped TiO₂ nanocrystals with enhanced photocatalytic activity for AO7 degradation under visible-light radiation ». New Journal of Chemistry 46, n^o 15 (2022) : 6878–84. http://dx.doi.org/10.1039/d2nj00817c.

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TiO2 nanocrystals co-doped with nitrogen and terbium exhibited extended light absorption, improved charge separation efficiency, and enhanced AO7 adsorption efficiency, giving rise to enhanced AO7 degradation activity which was 2× better than undoped TiO2 nanocrystals.

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