Tuning morphology, surface, and nanocrystallinity of rare earth vanadates by one-pot colloidal conversion of hydroxycarbonates

We present a facile one-pot synthesis to prepare ternaryZnxCd1-xSe(x= 0.2, 0.5, 0.8, and 1) nanocrystals (NCs) with high emission quantum yield (QY, 45~89%). The effect of Zn content (x) ofZnxCd1-xSeNCs on their physical properties is investigated. The NCs have a particle size of 3.2 nm and face centered cubic structure. However, the actual compositions of the NCs are Zn0.03Cd0.97Se, Zn0.11Cd0.89Se, and Zn0.38Cd0.62Se when Zn content is 0.2, 0.5, and 0.8, respectively. In terms of the optical properties, the emission wavelength shifts from 512 to 545 nm with increasing Zn content from 0 to 0.8 while the QY changes from 89 to 45, respectively. Partial replacement of Cd by Zn is beneficial to improve the QY of Zn0.2and Zn0.5NCs. The optical properties of ternary NCs are affected by compositional effect rather than particle size effect.

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ChemInform Abstract: Rare Earth Triflates/Chlorotrimethylsilane-Promoted One-Pot Synthesis of Enals.

ChemInform ◽

10.1002/chin.201424041 ◽

2014 ◽

Vol 45 (24) ◽

pp. no-no

Author(s):

Masahiro Toyota ◽

Natsuko Kagawa ◽

Yoshiko Sasaki ◽

Shoko Sakaguchi ◽

Ayumi Nagatomo ◽

...

Keyword(s):

Rare Earth ◽

One Pot ◽

One Pot Synthesis

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Growth and spectroscopic properties of rare-earth doped YAl3(BO3)4 single crystals

Journal of Luminescence ◽

10.1016/s0022-2313(02)00533-1 ◽

2003 ◽

Vol 102-103 ◽

pp. 395-401 ◽

Cited By ~ 29

Author(s):

I. Földvári ◽

E. Beregi ◽

A. Baraldi ◽

R. Capelletti ◽

W. Ryba-Romanowski ◽

...

Keyword(s):

Rare Earth ◽

Single Crystals ◽

Spectroscopic Properties ◽

Rare Earth Doped

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SiO2-SnO2:Er3+ Glass-Ceramic Monoliths

10.20944/preprints201807.0081.v1 ◽

2018 ◽

Author(s):

Lam Thi Ngoc Tran ◽

Damiano Massella ◽

Lidia Zur ◽

Alessandro Chiasera ◽

Stefano Varas ◽

...

Keyword(s):

Rare Earth ◽

Optical Sensors ◽

Tin Dioxide ◽

Sol Gel ◽

Glass Ceramics ◽

Building Blocks ◽

Spectroscopic Properties ◽

Silica Matrix ◽

Rare Earth Ions ◽

Planar Waveguides

The development of efficient luminescent systems, such as microcavities, solid state lasers, integrated optical amplifiers, optical sensors is the main topic in glass photonics. The building blocks of these systems are glass-ceramics activated by rare earth ions because they exhibit specific morphologic, structural and spectroscopic properties. Among various materials that could be used as nanocrystals to be imbedded in silica matrix, tin dioxide presents some interesting peculiarities, e.g. the presence of tin dioxide nanocrystals allows increase in both solubility and emission of rare earth ions. Here, we focus our attention on Er3+ - doped silica – tin dioxide photonic glass-ceramics fabricated by sol-gel route. Although the SiO2-SnO2:Er3+ could be fabricated in different geometrical systems: thin films, monoliths and planar waveguides we herein limit ourselves to the monoliths. The effective role of tin dioxide as luminescence sensitizer for Er3+ ions is confirmed by spectroscopic measurements and detailed fabrication protocols are discussed.

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Colloidal Silica/Poly(Methacrylsiloxane) Nanocomposite Particles: Synthesis, Characterization, and Application in Toners.

MRS Proceedings ◽

10.1557/opl.2014.231 ◽

2014 ◽

Vol 1663 ◽

Author(s):

Dmitry Fomitchev ◽

Russell Lewis ◽

Hairuo Tu ◽

Li Cheng ◽

Hajime Kambara ◽

...

Keyword(s):

Particle Size ◽

Colloidal Silica ◽

Silica Particles ◽

Laser Printer ◽

Mass Ratio ◽

One Pot ◽

New Class ◽

New Material ◽

Hydrophobic Treatment ◽

Hydrophobic Material

ABSTRACTWe report on a new class of materials for laser printer toner applications. These materials were prepared from methacrysilane-in-water emulsions stabilized with colloidal silica particles. In this elegant system, the colloidal silica particles reside at the water/oil interface helping to emulsify the oil droplet, self-organizing into a raspberry-like morphology. The emulsion formation is followed by free-radical polymerization, hydrophobic treatment, and drying steps. This one pot synthesis in water affords a hydrophobic material with a particle size in the range of 80 to 300 nm. The particle size could be fine-tuned by changing the oil-to-silica mass ratio or by using colloidal silica particles of different sizes. Results of material characterization by solid-state NMR, electron microscopy, and particle size measurements methods will be presented. Examples of possible extensions of the synthesis towards materials with methacrylsilane partially substituted with other methacrylates will be provided. Application of the new material in toners will be described as will the comparison of its performance with the incumbent material - hydrophobic colloidal silica.

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Formation of ZnO/Zn0.5Cd0.5Se Alloy Quantum Dots in the Presence of High Oleylamine Contents

Nanomaterials ◽

10.3390/nano9070999 ◽

2019 ◽

Vol 9 (7) ◽

pp. 999

Author(s):

Yi-An Chen ◽

Kuo-Hsien Chou ◽

Yi-Yang Kuo ◽

Cheng-Ye Wu ◽

Po-Wen Hsiao ◽

...

Keyword(s):

Electron Microscopy ◽

Quantum Dots ◽

Particle Size ◽

X Ray Diffraction ◽

One Pot ◽

X Ray ◽

Transmission Electron ◽

Average Size ◽

Alloy Quantum Dots ◽

First Time

To the best of our knowledge, this report presents, for the first time, the schematic of the possible chemical reaction for a one-pot synthesis of Zn0.5Cd0.5Se alloy quantum dots (QDs) in the presence of low/high oleylamine (OLA) contents. For high OLA contents, high-resolution transmission electron microscopy (HRTEM) results showed that the average size of Zn0.5Cd0.5Se increases significantly from 4 to 9 nm with an increasing OLA content from 4 to 10 mL. First, [Zn(OAc)2]–OLA complex can be formed by a reaction between Zn(OAc)2 and OLA. Then, Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) data confirmed that ZnO is formed by thermal decomposition of the [Zn(OAc)2]–OLA complex. The results indicated that ZnO grew on the Zn0.5Cd0.5Se surface, thus increasing the particle size. For low OLA contents, HRTEM images were used to estimate the average sizes of the Zn0.5Cd0.5Se alloy QDs, which were approximately 8, 6, and 4 nm with OLA loadings of 0, 2, and 4 mL, respectively. We found that Zn(OAc)2 and OLA could form a [Zn(OAc)2]–OLA complex, which inhibited the growth of the Zn0.5Cd0.5Se alloy QDs, due to the decreasing reaction between Zn(oleic acid)2 and Se2−, which led to a decrease in particle size.

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Biocompatibility and Biodistribution of Several Nano-Sized Ceramics Particles

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.529-530.625 ◽

2012 ◽

Vol 529-530 ◽

pp. 625-629

Author(s):

Shigeaki Abe ◽

Yusaku Hamba ◽

Nobuki Iwadera ◽

Tsukasa Akasaka ◽

Shuichi Yamagata ◽

...

Keyword(s):

Particle Size ◽

Rare Earth ◽

Size Effect ◽

Rare Earth Element ◽

Earth Element ◽

Chemical Species ◽

Osteoblastic Cell ◽

Tail Vein

We succeeded in determination the biodistribution of several nano-sized particles administered to mice through the tail vein. After administration, these particles were observed in the lung, liver and spleen. The distribution behaviors depend upon not only chemical species but also the particles size. To estimate their cytocompatibility, these particles were exposed to osteoblastic cell at several concentrations. When the concentration reached at 10 ppm, their viability remained at 80% or more even nano-sized particle contained rare earth element. Only CuO particles indicated the viability decrease. The effect depended on the particle size. These results suggested that the chemical species played a dominant key in the biodistribution and biocompatibility of nanoparticles compared with the size-effect.

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The magnetic and spectroscopic properties of certain rare-earth double nitrates

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1955.0231 ◽

1955 ◽

Vol 232 (1191) ◽

pp. 458-474 ◽

Cited By ~ 72

Keyword(s):

Rare Earth ◽

Electric Field ◽

Spectroscopic Properties ◽

Rare Earth Ions ◽

Rare Earth Ion ◽

Crystalline Electric Field ◽

Paramagnetic Resonance ◽

Systematic Fashion ◽

Resonance Data ◽

Rare Earth Series

The theory that has been developed for rare-earth ions in crystals is here applied to the double nitrates. The paramagnetic resonance data and certain spectroscopic properties of the different rare-earth double nitrates, depending as they do on the crystalline electric field at a rare-earth ion, are related to the six parameters through which the field is defined. It is found that most of the experimental results can be fitted to values of the parameters that vary in a systematic fashion along the rare-earth series.

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