T:toxic;
7784-18-1Relevant articles and documents
Electron-beam induced crystallization transition in self-developing amorphous AIF3 resists
Chen,Boothroyd,Humphreys
, p. 170 - 172 (1996)
Transmission electron microscopy is used to investigate electron-induced crystallization of thermally evaporated amorphous AlF3(α-AlF3). It is shown that this material undergoes a very complicated crystallization process with three crystalline substances (Al, AlF3, and Al2O3) formed as the dose increases. The sequence of the crystallization is highly sensitive to the presence of water, which inhibits radiolytic dissociation of α-AlF3 into Al and fluorine, reduces the dose required for the crystallization of α-AlF3, and causes the transformation of AlF3 into Al2O3.
Improvement of the electrochemical properties of Li [Ni0.5 Mn0.5] O2 by AlF3 coating
Sun, Yang-Kook,Myung, Seung-Taek,Park, Byung-Chon,Yashiro, Hitoshi
, p. A705-A710 (2008)
An ～10 nm AlF3 layer was coated on the surface of a Li [Ni 0.5Mn0.5]O2 positive electrode material for lithium-ion batteries, and the effects of this coating on battery performances and thermal stability of the cathode materials were studied. Although no significant bulk structural differences were observed between the coated and pristine material, a slightly higher capacity was seen for the AlF3 -coated Li [Ni0.5Mn0.5]O2 electrode, and the rate capability was also greatly enhanced by the AlF3 coating. These improvements are mainly attributed to the suppression of the transition metal dissolution benefited from the AlF3 coating. This suppression contributed to the reduction in the charge-transfer resistance. Time-of-flight secondary ion mass spectroscopic analysis showed that insulating LiF, as a product of decomposed LiPF6, was deposited on the surface of pristine and AlF3 -coated Li [Ni0.5Mn0.5]O2. The deposition of LiF was greatly suppressed by AlF3 coating on the outer surface of Li [Ni0.5Mn0.5]O2. The protection of the active material by the AlF3 coating substantially improved the capacity, capacity retention, and rate capability of the batteries. It also enhanced the thermal stabilities of the positive electrode material.
Characterization of four phase transitions in Pb5Al3F19, including a new transition at 670 K, by impedance and NMR spectroscopy
El Omari,Reau,Senegas,Ravez,Abrahams,Nadiri,Yacoubi
, p. 2896 - 2902 (1998)
X-ray diffraction, thermal, optical, and dielectric studies of Pb5Al3F19 undertaken previously between 100 and 400 K showed this material undergoes three phase transitions. The four known phases are ferroelectric phase V, with a transition to antiferroelectric phase IV at 270 K on heating, 140 K on cooling. The transition from phase IV to ferroelastic phase III is at 320 K on heating, 305 K on cooling; that from phase III to paraelastic phase II is at 360 K without thermal hysteresis. Impedance and NMR spectroscopy in the complementary temperature ranges 279-743 and 125-430 K characterized the influence of these phases on the ionic conductivity and F- ion diffusion properties in this material.
Reactivity of fluorinated γ-alumina and β-aluminium(III) fluoride surfaces towards hydrogen halides and tert-butyl chloride
Barclay, Christopher H.,Bozorgzadeh, Hamid,Kemnitz, Erhard,Nickkho-Amiry, Mahmood,Ross, Debbie E.M.,Skapin, Tomaz,Thomson, James,Webb, Geoffrey,Winfield, John M.
, p. 40 - 47 (2002)
The Lewis acids β-aluminium(III) fluoride and γ-alumina, fluorinated at room temperature with sulfur, tetrafluoride, both interact with hydrogen fluoride and chloride, as demonstrated by radiotracer measurements using [18F] and [36Cl
Thermal and XRD analysis of synthesis of fluoro-topaz
Abdel-Rehim
, p. 29 - 35 (2012)
The present work deals with thermal and XRD analysis of fluoro-topaz synthesis by sintering of aluminium and silicon oxides (in the form of corundum and quartz) with ammonium fluoride and carried out in open Pt crucibles (for XRD studies) and a closed furnace of simultaneous DTA/TG thermoanalytical apparatus called MOM Derivatograph. The furnaces are connected to a gas suction device to remove gas decomposition products. The study shows the endothermic peak at 125-155°C, representing the formation of ammonium aluminium hexafluoride and cryptohalite. The endothermic peak at 220-240°C represents the beginning of dissociation of ammonium aluminium hexafluoride to the more stable ammonium aluminium tetrafluoride. The endothermic peak at 340-350°C represents the dissociation of cryptohalite and ammonium aluminium tetrafluoride with the formation of aluminium fluoride. The formation of fluoro-topaz is represented by the wide endothermic peak at 770-800°C. The medium wide or sharp endothermic peaks at 950°C and 1000°C represent the subsequent dissociation of fluoro-topaz to corundum or mullite, respectively.
Zeolite catalysts for Halon conversion
Howe,Lee,Thomson,Kennedy,Yang,Dlugogorski
, p. 63 - 72 (2002)
The chemical states of Al and Ni in NiZSM-5 catalyst used for the pyrolysis and hydrodehalogenation with methane of Halon 1301 (CF3Br) were characterized using Al and Ni K-edge XANES and EXAFS experiments. Reaction products were CF4
Vibrational analysis study of aluminum trifluoride phases
Gross, Udo,Ruediger, Stephan,Kemnitz, Erhard,Brzezinka, Klaus-Werner,Mukhopadhyay, Sanghamitra,Bailey, Christine,Wander, Adrian,Harrison, Nicholas
, p. 5813 - 5819 (2007)
The vibrational modes of three solid AlF3 phases (α, β, and amorphous high surface area AlF3) are investigated. Calculations have been performed using hybrid exchange correlation functionals to determine the equilibrium geometries an
The effects of AlF3 coating on the performance of Li[Li 0.2 Mn0.54 Ni0.13 Co0.13]O 2 positive electrode material for lithium-ion battery
Zheng,Zhang,Wu,Dong,Zhu,Yang
, p. A775-A782 (2008)
Al F3 -coated Li [Li0.2 Mn0.54 Ni0.13 Co0.13] O2 materials have been synthesized as positive electrode materials for lithium-ion batteries. The pristine and Al F3 -coated Li [Li0.2 Mn0.54 Ni0.13 Co0.13] O2 materials were characterized by X-ray diffraction
AlF3-coating to improve high voltage cycling performance of Li[Ni1/3Co1/3Mn1/3]O2 cathode materials for lithium secondary batteries
Sun,Cho,Lee,Yoon,Amine
, p. A168-A172 (2007)
Li [Ni13 Co13 Mn13] O2 powders were modified by coating their surface with amorphous AlF3 as a new coating material. The AlF3 -coated Li [Ni13 Co13 Mn13] O2 electrode showed improved cycle performance and rate capability under a high cutoff voltage range of 4.5 and 4.6 V. AC impedance results showed that the AlF3 -coated Li [Ni13 Co13 Mn13] O2 has stable charge transfer resistance (Rct) regardless of the cycle number. Electron diffraction analysis also showed that no structural transition of the primary particles was observed for the AlF3 -coated electrode. Electrochemical impedance spectroscopy and electron microscopy indicate that AlF3 coating plays an important role of stabilizing the interface between cathode and electrolyte.
CaF2-AlF3-SiO2 glass-ceramic with low dielectric constant for LTCC application
Wang, Rui,Zhou, Ji,Li, Bo,Li, Longtu
, p. 204 - 207 (2010)
Low temperature co-fired ceramic (LTCC) materials based on CaF2-AlF3-SiO2 oxyfluoride glass-ceramics were prepared. The sintering behaviors, phase transition, microstructures, and the dielectric properties of the glass-cer
