Probing Crystallization Studying Amorphous Phase Evolution

Aluminum phosphate is one of the best inorganic binders, and the addition of chromium oxide can improve the properties of the binder. In this work, the phase evolutions in chromium phosphate system and aluminum-chromium-phosphate system during heat-treatment were investigated. The initial binder solutions were prepared by dissolving Al(OH)3 and Cr2O3 in aqueous H3PO4 solution. The binder solutions consolidated at 100°C. The as-consolidated products were heated at different temperature. The experimental results showed the phase evolution of the consolidated products as: amorphous phase in 300~800°C, Cr(PO3)3 and Cr4(P2O7)3 in 900~1200°C for chromium phosphate system binder; amorphous phase in 300~1000°C, Cr(PO3)3 and AlPO4 in 1100°C, Cr4(P2O7)3 and AlPO4 in 1200°C for aluminumchromium- phosphate system binder. The addition of chromium oxide demonstrates to strengthen amorphous network, which further improves the thermal stability.

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Evolution of metastable phases during crystallization of pulsed laser deposited amorphous Al–Fe films

Journal of Materials Research ◽

10.1557/jmr.2003.0040 ◽

2003 ◽

Vol 18 (2) ◽

pp. 284-295 ◽

Cited By ~ 3

Author(s):

Sandip Bysakh ◽

Puspendu Kumar Das ◽

Kamanio Chattopadhyay

Keyword(s):

Amorphous Phase ◽

Pulsed Laser ◽

Phase Evolution ◽

The Body ◽

Metastable Phases ◽

Cubic Phase ◽

Amorphous Thin Films ◽

Transmission Electron ◽

Ordered Phases ◽

Vapor Quenching

Amorphous thin films of different Al–Fe compositions were produced by plasma/vapor quenching during pulsed laser deposition. The chosen compositions Al72Fe28, Al40Fe60, and Al18Fe82 correspond to Al5Fe2 and B2-ordered AlFe intermetallic compounds and α–Fe solid solution, respectively. The films contained fine clusters that increased with iron content. The sequences of phase evolution observed in the heating stage transmission electron microscopy studies of the pulsed laser ablation deposited films of Al72Fe28, Al40Fe60, and Al18Fe82 compositions showed evidence of composition partitioning during crystallization for films of all three compositions. This composition partitioning, in turn, resulted in the evolution of phases of compositions richer in Fe, as well as richer in Al, compared to the overall film composition in each case. The evidence of Fe-rich phases was the B2 phase in Al72Fe28 film, the L12- and DO3-ordered phases in Al40Fe60 film, and the hexagonal ε–Fe in the case of the Al18Fe82 film. On the other hand, the Al-rich phases were Al13Fe4 for both Al72Fe28 and Al40Fe60 films and DO3 and Al5Fe2 phases in the case of Al18Fe82 film. We believe that this tendency of composition partitioning during crystallization from amorphous phase is a consequence of the tendency of clustering of the Fe atoms in the amorphous phase during nucleation. The body-centered cubic phase has a nucleation advantage over other metastable phases for all three compositions. The amorphization of Al18Fe82 composition and the evolution of L12 and ε–Fe phases in the Al–Fe system were new observations of this work.

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Amorphous phase evolution during crystallization of poly(ethylene-terephthalate)

Colloid & Polymer Science ◽

10.1007/bf01095058 ◽

1992 ◽

Vol 270 (12) ◽

pp. 1182-1187 ◽

Cited By ~ 23

Author(s):

G. Vigier ◽

J. Tatibouet ◽

A. Benatmane ◽

R. Vassoille

Keyword(s):

Amorphous Phase ◽

Ethylene Terephthalate ◽

Phase Evolution ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene

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Unraveling the unstable amorphous phase evolution effect on burn-in loss in polymer-fullerene solar cells

Organic Electronics ◽

10.1016/j.orgel.2019.05.020 ◽

2019 ◽

Vol 71 ◽

pp. 156-163 ◽

Cited By ~ 4

Author(s):

Xiao-Yu Yang ◽

Meng-Si Niu ◽

Chaochao Qin ◽

Peng-Qing Bi ◽

Zhi-Hao Chen ◽

...

Keyword(s):

Solar Cells ◽

Amorphous Phase ◽

Phase Evolution ◽

Evolution Effect

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Phase Selection During Interdiffusion in Ti-Fe Multilayered Films

MRS Proceedings ◽

10.1557/proc-311-79 ◽

1993 ◽

Vol 311 ◽

Cited By ~ 1

Author(s):

Z.Z. Yan ◽

M.M. Trudeau ◽

R. Schulz ◽

R. Bormann ◽

A.Van Neste ◽

...

Keyword(s):

Solid Solution ◽

Amorphous Phase ◽

Phase Evolution ◽

Calphad Method ◽

Interfacial Structure ◽

X Ray Diffraction ◽

Multilayered Films ◽

Phase Selection ◽

Kinetics And Thermodynamics ◽

X Ray

ABSTRACTThe formation of the metastable bcc solid solution and the amorphous phase during interfacial reaction of elemental multilayers has been studied using X-ray diffraction. Different kinds of interfaces have been synthesized in order to investigate the influence of the interfacial structure on phase evolution during annealing. The amorphization is found to be dependent on the structure of the interface and the results are discussed in terms of the kinetics and thermodynamics of the Ti-Fe system which has been calculated by the CALPHAD method.

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Complex phase evolution of Brushite-based calcium phosphate CaHPO4·2H2O using in situ high temperature X-ray diffraction and thermal analysis

10.21203/rs.3.rs-44209/v1 ◽

2020 ◽

Author(s):

Mouatamid El Hazzat ◽

Adnane El Hamidi ◽

Mohammed Halim ◽

said ARSALANE

Keyword(s):

Thermal Analysis ◽

Infrared Spectroscopy ◽

High Temperature ◽

Calcium Phosphate ◽

Amorphous Phase ◽

Phase Evolution ◽

High Temperature Treatment ◽

X Ray Diffraction ◽

X Ray

Abstract This study focused on a detailed examination of the thermal behavior of Brushite-based calcium phosphate (CaHPO 4 .2H 2 O, DCPD) to identify and characterize the intermediate phases which have been the subject of previous several controversies. For that, in situ high-temperature X-ray diffraction supported by infrared spectroscopy, thermal analysis, and scanning electron microscopy analysis were used and the results showed that the progressive thermal stress of DCPD in air resulted in a heterogeneous formulation consisting of dibasic calcium phosphate anhydrous (CaHPO 4 , DCPA) and an amorphous phase, which appears at low temperatures (~160 °C) and persists up to 375 °C. The deep examination of the amorphous phase by infrared spectroscopy revealed that its chemical composition is similar to that of disordered calcium pyrophosphate (Ca 2 P 2 O 7 , CPP) with the appearance of a characteristic band δ(P-O-P), located at 740 cm -1 . This IR band is shifted to low frequencies (725 cm -1 ) as the temperature is increased, indicating the crystallization of the amorphous phase into γ-CPP. The high temperature treatment (≥ 375 °C) leads to b-CPP polymorph. According to the present characterization results, obtaining pure DCPA from the thermal dehydration of DCPD is not effective and leads to biphasic materials including an amorphous phase.

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Simultaneous crystalline-amorphous phase evolution during crystallization of polymer systems

EPL (Europhysics Letters) ◽

10.1209/epl/i2002-00211-3 ◽

2002 ◽

Vol 59 (3) ◽

pp. 417-422 ◽

Cited By ~ 19

Author(s):

T. A Ezquerra ◽

I Šics ◽

A Nogales ◽

Z Denchev ◽

F. J Baltá-Calleja

Keyword(s):

Amorphous Phase ◽

Phase Evolution ◽

Polymer Systems

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Chemical Availability of Bromide Dictates CsPbBr3 Nanocrystal Growth

10.26434/chemrxiv.8081504 ◽

2019 ◽

Author(s):

Je-Ruei Wen ◽

Benjamin Roman ◽

Freddy Rodriguez Ortiz ◽

Noel Mireles Villegas ◽

Nicholas Porcellino ◽

...

Keyword(s):

Reaction Time ◽

Growth Mechanism ◽

Chemical Control ◽

Critical Role ◽

Phase Evolution ◽

Detailed Understanding ◽

Semiconductor Nanocrystal ◽

Nanocrystal Growth ◽

Chemical Availability

Lack of detailed understanding of the growth mechanism of CsPbBr3 nanocrystals has hindered sophisticated morphological and chemical control of this important emerging optoelectronic material. Here, we have elucidated the growth mechanism by slowing the reaction kinetics. When 1-bromohexane is used as an alternative halide source, bromide is slowly released into the reaction mixture, extending the reaction time from ~3 seconds to greater than 20 minutes. This enables us to monitor the phase evolution of products over the course of reaction, revealing that CsBr is the initial species formed, followed by Cs4PbBr6, and finally CsPbBr3. Further, formation of monodisperse CsBr nanocrystals is demonstrated in a bromide-deficient and lead-abundant solution. The CsBr can only be transformed into CsPbBr3 nanocubes if additional bromide is added. Our results indicate a fundamentally different growth mechanism for CsPbBr3 in comparison with more established semiconductor nanocrystal systems and reveal the critical role of the chemical availability of bromide for the growth reactions.<br>

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Structure of Amorphous Phase and Nanocrystalline Phases in the Devitrification of Iron Alloys

Steel in Translation ◽

10.3103/s096709121905005x ◽

2019 ◽

Vol 49 (5) ◽

pp. 361-364

Author(s):

N. B. D’yakonova ◽

D. L. D’yakonov ◽

B. A. Kornienkov ◽

V. P. Filippova

Keyword(s):

Amorphous Phase ◽

Iron Alloys ◽

Nanocrystalline Phases

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The Application of X-Ray Diffraction at Elevated Temperatures to Study the Mechanism of Formation of Sodium Tripolyphosphate

Advances in X-ray Analysis ◽

10.1154/s0376030800001634 ◽

1961 ◽

Vol 5 ◽

pp. 276-284

Author(s):

E. L. Moore ◽

J. S. Metcalf

Keyword(s):

High Temperature ◽

Low Temperature ◽

Amorphous Phase ◽

Elevated Temperatures ◽

Sodium Tripolyphosphate ◽

X Ray Diffraction ◽

Mechanism Of Formation ◽

X Ray ◽

Temperature Form ◽

High Temperature Form

AbstractHigh-temperature X-ray diffraction techniques were employed to study the condensation reactions which occur when sodium orthophosphates are heated to 380°C. Crystalline Na4P2O7 and an amorphous phase were formed first from an equimolar mixture of Na2HPO4·NaH2PO4 and Na2HPO4 at temperatures above 150°C. Further heating resulted in the formation of Na5P3O10-I (high-temperature form) at the expense of the crystalline Na4P4O7 and amorphous phase. Crystalline Na5P3O10-II (low-temperature form) appears after Na5P3O10-I.Conditions which affect the yield of crystalline Na4P2O7 and amorphous phase as intermediates and their effect on the yield of Na5P3O10 are also presented.

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