Phase transition kinetics of LiNi0.5Mn1.5O4 electrodes studied by in situ X-ray absorption near-edge structure and X-ray diffraction analysis

A 2-2-type nanostructure bilayer film of CoFe2O4/Pb(Zr0.52Ti0.48)O3 was successfully prepared on the (111)Pt/Ti/SiO2/Si substrate. The Pb(Zr0.52Ti0.48)O3 layer in the bilayer film is (111) oriented and is a mixture of tetragonal and monoclinic phases. The results from an in situ X-ray diffraction analysis of the multiferroic bilayer film under statistic magnetic field indicate that the monoclinic-tetragonal phase transition was induced by magnetostriction of the CoFe2O4 layer. A large magnetoelectric effect was obtained probably because of the different polarization directions of the tetragonal and monoclinic phases.

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In Situ Rapid Thermal Hydrogenation Pretreatment of Ti for Salicide RTA

MRS Proceedings ◽

10.1557/proc-429-187 ◽

1996 ◽

Vol 429 ◽

Author(s):

K. Ando ◽

T. Ishigami ◽

Y. Matsubara ◽

T. Horiuchi ◽

S. Nishimoto

Keyword(s):

Crystal Structure ◽

Phase Transition ◽

Diffraction Analysis ◽

Sheet Resistance ◽

Rapid Thermal Annealing ◽

Titanium Silicide ◽

Silicide Formation ◽

X Ray Diffraction ◽

X Ray

AbstractAn in situ rapid thermal hydrogenation (RTH) pretreatment of titanium prior to rapid thermal annealing (RTA), or RTH/RTA, is proposed as a silicide formation annealing in a CMOS self-aligned silicide (salicide) process. The in situ RTH is found to enhance silicidation, to reduce nitridation, and even to lower the resultant sheet resistance of titanium silicide.During in situ RTH (e.g., at 550°C), amorphous Ti silicide (e.g., 15-nm thick) grows selectively on Si. Furthermore, Ti nitridation during subsequent RTA (690°C, N2, 10 Torr, 30 s) is reduced depending on RTH (H2, 10 Torr, 30 s) temperature. Accordingly, for 550°C RTH and an initial Ti thickness of 15 nm, the sheet resistance obtained at the 0.27-μm-wide n+ poly-Si gate after a phase transition annealing (800°C, Ar, 10 s) was lower (11.7 Ω /□, st. dev. = 6%) than that of conventional Ti silicide (15.8 Ω/□, st. dev. = 10%). The silicidation enhancement and nitridation reduction are related to crystal structure metamorphosis or to hydrogen interstitial incorporation in the Ti layer during RTH as observed by x-ray diffraction analysis. It is concluded that in situ RTH pretreatment before RTA is very promising as a sub-quarter-micron CMOS salicide process.

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Oxygen Reduction Contributing to Charge Transfer during the First Discharge of the CeO2–Bi2Fe4O9–Li Battery: In Situ X-ray Diffraction and X-ray Absorption Near-Edge Structure Investigation

The Journal of Physical Chemistry C ◽

10.1021/jp4105689 ◽

2014 ◽

Vol 118 (27) ◽

pp. 14711-14722 ◽

Cited By ~ 10

Author(s):

Min Liu ◽

Chuan Lin ◽

Yueliang Gu ◽

Tieying Yang ◽

Zhengliang Gong ◽

...

Keyword(s):

Charge Transfer ◽

Oxygen Reduction ◽

Structure Investigation ◽

X Ray Diffraction ◽

Edge Structure ◽

X Ray ◽

Li Battery ◽

X Ray Absorption

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Studies on the β → α Phase Transition Kinetics of Ti–3.5Al–5Mo–4V Alloy under Isothermal Conditions by X-ray Diffraction

Metals ◽

10.3390/met10010090 ◽

2020 ◽

Vol 10 (1) ◽

pp. 90

Author(s):

Panpan Ge ◽

Song Xiang ◽

Yuanbiao Tan ◽

Xuanming Ji

Keyword(s):

Phase Transition ◽

Aging Time ◽

Solution Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Α Phase ◽

Precipitate Fraction ◽

Transformation Mechanisms ◽

Phase Transition Kinetics ◽

Kinetics Of

The β → α phase transition kinetics of the Ti–3.5Al–5Mo–4V alloy with two different grain sizes was investigated at the isothermal temperature of 500 °C. A method to estimate the function of the precipitate fraction of the α phase with different aging times was developed based on X-ray diffraction analysis. The value of the α precipitate fraction increased sharply at first, then increased slowly with the aging time, and finally reached equilibrium. The value of the α precipitate fraction was higher in the alloy aged for the same time at a higher solution temperature, while the size of the α precipitate was smaller at a higher solution temperature. The β → α phase transition kinetics under isothermal conditions were modeled in the theoretical frame of the Johnson–Mehl–Avrami–Kolmogorov (JMAK) theory. The kinetic parameters of JMAK deduced different transformation mechanisms. The mechanism of the phase transition in the first stage was dominated by mixed transformation mechanisms (homogeneously nucleated and acicular-grown α structure, and grain boundary-nucleated and grown α precipitate), while the second stage was the growth of the fine α precipitate, which was controlled by slow diffusion. As the aging time increased, the hardness of the Ti–3.5Al–5Mo–4V alloy increased sharply. After the hardness of the alloy reached a plateau, it began to decline. The hardness of the alloy was always higher at a higher solution temperature.

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