High-Yield Synthesis of Rhombohedral Boron Nitride Triangular Nanoplates.

ChemInform ◽  
2007 ◽  
Vol 38 (43) ◽  
Author(s):  
Liqiang Xu ◽  
Jinhua Zhan ◽  
Junqing Hu ◽  
Yoshio Bando ◽  
Xiaoli Yuan ◽  
...  
2007 ◽  
Vol 19 (16) ◽  
pp. 2141-2144 ◽  
Author(s):  
L. Q. Xu ◽  
J.   H. Zhan ◽  
J. Q. Hu ◽  
Y. Bando ◽  
X. L. Yuan ◽  
...  

Author(s):  
Udayakumar Veerabagu ◽  
Gowsika Jaikumar ◽  
Fushen Lu ◽  
Franck Quero

The 3 wt% CuI/BNNS catalyst exhibited high efficiency for C–H difluoromethylation reactions and enabled greener synthesis at high yields using cyrene as a solvent. Furthermore, the catalyst could be easily recovered and recycled for at least five cycles.


2020 ◽  
Author(s):  
Laurent Souqui ◽  
Justinas Palisaitis ◽  
Naureen Ghafoor ◽  
Henrik Pedersen ◽  
Hans Högberg

<div>Epitaxial rhombohedral boron nitride films were deposited on ZrB<sub>2</sub>(0001)/4H-SiC(0001) by chemical vapor deposition at 1485 °C from the reaction of triethylboron and ammonia and with a minute amount of silane (SiH<sub>4</sub>). X-ray diffraction (XRD) φ-scans yield the epitaxial relationships of 𝑟−𝐵𝑁(0001)∥𝑍𝑟𝐵2(0001) out-of-plane and 𝑟−𝐵𝑁(1120)∥𝑍𝑟𝐵2(1120) in-plane. Cross-section transmission electron microscopy (TEM) micrographs showed that epitaxial break down of r-BN film occurs approximatively after 10 nm, above which epitaxial growth proceeds only in limited area up to 80 nm of film thickness. Both XRD and TEM demonstrate the formation of carbon- and nitrogen-containing cubic inclusions at the ZrB<sub>2</sub> surface. Quantitative analysis from X-ray photoelectron spectroscopy of the r-BN films shows B/N ratios between 1.30 to 1.20 and an O content of 3 to 4 at.%. Plan-view scanning electron microscopy (SEM) images reveal a surface morphology where an amorphous material comprising B, C, and N is surrounding the epitaxial twinned r-BN crystals. SiH<sub>4</sub> exposure prior to growth was found to reduce the amount of the amorphous phase on the surface. Defects such as pitting were also observed on the ZrB<sub>2</sub> template surface.</div><div><br></div>


2018 ◽  
Author(s):  
Laurent Souqui ◽  
Henrik Pedersen ◽  
Hans Högberg

Epitaxial rhombohedral boron nitride films were deposited on α-Al2O3(001) substrates by chemical vapor deposition, using trimethylboron, ammonia, and with a low concentration of silane in the growth flux. The depositions were performed at temperatures from 1200 to 1485 °C, pressures from 30 to 90 mbar and N/B ratios from 321 to 1286. The most favorable conditions for epitaxy were: a temperature of 1400 °C, N/B around 964, and pressures below 40 mbar. Analysis by thin film X-ray diffraction showed that most deposited films were polytype-pure epitaxial r-BN with an out-of-plane epitaxial relationship of r-BN[001]∥ w-AlN[001]∥ α-Al2O3[001] and with two in-plane relationships of r-BN[110]∥ w-AlN[110]∥ α-Al2O3[100] and r-BN[110]∥ w-AlN[110]∥ α-Al2O3[1̅00] due to twinning.


2011 ◽  
Vol 21 (24) ◽  
pp. 8694 ◽  
Author(s):  
Samuel Bernard ◽  
Vincent Salles ◽  
Junping Li ◽  
Arnaud Brioude ◽  
Mikhael Bechelany ◽  
...  
Keyword(s):  

2011 ◽  
Vol 21 (28) ◽  
pp. 10268 ◽  
Author(s):  
Gabriel Maria Ingo ◽  
Giuseppina Padeletti ◽  
Tilde de Caro ◽  
Cristina Riccucci ◽  
Federica Faraldi ◽  
...  

2019 ◽  
Vol 90 (5-6) ◽  
pp. 512-522 ◽  
Author(s):  
Hong Liu ◽  
Yang Du ◽  
Shaohua Lei ◽  
Zhuoqun Liu

Boron nitride nanosheets (BNN) were prepared by molten hydroxide-assisted liquid exfoliation from hexagonal boron nitride powder with an effectively high yield, and then modified with hexachlorocyclotriphosphazene (HCCP) to obtain HCCP-BNN. The series of samples were applied to prepare flame-retardant cotton fabrics with the impregnation-drying method, and successful treatment was confirmed by scanning electron microscopy. The combustion performance of the as-prepared cotton fabrics was tested and evaluated. After coating with HCCP-BNN, the combustion rate of the fabric is reduced in vertical and horizontal combustion conditions and the limiting oxygen-index value of cotton fabric increases to 24.1, becoming less flammable than the blank cotton. The fibrous structure of the BNN and HCCP-BNN coated fabrics is relatively complete after combustion, which indicates that BNN have a certain protective effect on the fabric. The results demonstrate HCCP-BNN as an effective flame-retardant for cotton fabrics.


1995 ◽  
Vol 51 (15) ◽  
pp. 10264-10264 ◽  
Author(s):  
D. L. Medlin ◽  
T. A. Friedmann ◽  
P. B. Mirkarimi ◽  
M. J. Mills ◽  
K. F. McCarty

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