The crystallographic template effect assisting the formation of stable α-Al2O3 during low temperature oxidation of Fe–Al alloys

Brito, Pedro; Pinto, Haroldo Cavalcanti; Kostka, Aleksander

doi:10.1016/j.corsci.2016.01.007

Cited by 34 publications

(7 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This provides a crucial mechanistic understanding of the large O 2 release from the aforesaid instantaneous solid−solid phase transitions, prompted by the thermal decomposition of interfacial stabilizing C skins leading to the simultaneous release of the excess CO 2 . Subsequent HRTEM examination of the final TGA burn byproducts in Figure 5b (inset for SAED patterns) indicates the final products to be highly crystalline α-Al 2 O 3 particles with characteristic d-spacing of ∼0.209 nm, 49 which supports our earlier HTXRD data in Figure 4a.…”

Section: Resultssupporting

confidence: 82%

Laser-Induced Trapping of Metastable Amorphous AlO_x/C (2.5 < x ≤ 3.5) Nanocomposites: Implications for Use as Solid Phase Gas Generators

Davis

Duscher

Wen

et al. 2023

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

The synthesis of kinetically “frozen” metastable nanostructures remains elusive. This limitation has severely restricted the current paradigms in materials discovery. We overcame this challenge by phase-stabilizing unusually hyperoxidized and metastable amorphous aluminum oxide (a-AlO x ; 2.5 < x ≤ 3.5) nanostructures. Specifically, we employed laser ablation synthesis in solution (LASiS) as a one-pot nonequilibrium technique to achieve this pivotal advancement. Structural and compositional characterizations of the as-synthesized material reveal highly disordered a-AlO x nanoparticles that are remarkably stabilized by interfacial monolayers of ordered carbon atoms. Both structure and chemical composition were confirmed with disparate characterization methods at different length scales. The nanoparticles of sizes less than 10 nm were stable even at elevated temperatures. Only at temperatures higher than 750 °C do the a-AlO x structures undergo a solid–solid phase transition that culminates in the formation of stable α-Al2O3 while releasing excess trapped gases. Such disruptive materials can find applications in emerging technologies seeking metastable phase-change materials for solid phase gas generators, batteries, neuromorphic computing, and energetic additives.

show abstract

Section: Resultssupporting

confidence: 82%

Laser-Induced Trapping of Metastable Amorphous AlO_x/C (2.5 < x ≤ 3.5) Nanocomposites: Implications for Use as Solid Phase Gas Generators

Davis

Duscher

Wen

et al. 2023

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

show abstract

“…We also found that the transformation to a-Al 2 O 3 was promoted on binary Fe-Al alloys with higher Fe content [17]. P. Brito et al also found same beneficial effect of Fe on promoting a-Al 2 O 3 scale formation on the binary Fe-Al alloys at lower temperature, 700°C [18]. However, it was difficult to clarify which element, Fe or Al, had a stronger effect on the transformation since Fe and Al contents cannot be changed independently in the binary Fe-Al system.…”

Section: Introductionsupporting

confidence: 52%

Metastable-Stable Phase Transformation Behavior of Al2O3 Scale Formed on Fe–Ni–Al Alloys

et al. 2016

View full text Add to dashboard Cite

The oxidation behavior of Ni-Fe-41.5at.%Al alloys with different Fe/Ni ratios was investigated in air at 1000°C in order to clarify the effect of Fe on the phase transformation of Al 2 O 3 scale, using in-situ high-temperature X-ray diffraction by means of synchrotron radiation. The oxidation mass gain of alloys after 25 h of oxidation generally decreased with increasing Fe content; however, the initial oxidation mass gain was significantly decreased by increasing alloy Fe content. Insitu X-ray diffraction analysis indicated that higher alloy Fe contents promoted rapid formation of the stable a-Al 2 O 3 , while lower Fe in the alloy maintained the metastable Al 2 O 3 for longer time oxidation. The effect of Fe on promoting a-Al 2 O 3 formation can be explained by the initial formation of a-Fe 2 O 3 , whose structure is isomorphous with a-Al 2 O 3 . The additional effect of Fe on the growth rate of a-Al 2 O 3 is also discussed.

show abstract

“…Even more easily, α-Al 2 O 3 can be obtained on appropriate seed layers where the Al 2 O 3 films are deposited on. For instance, α-Al 2 O 3 has been grown at 1000 °C on Ti(C,N) and Ti 3 O 5 /Ti 4 O 7 surfaces by chemical vapor deposition (CVD), ,,, at 700 °C on α-Fe 2 O 3 formed during thermal oxidation of metal alloys that contain Fe and Al, and at 700–750 °C on CrN in magnetron sputtering (MS) experiments . Using the MS method and α-Al 2 O 3 as a component of a sputtering target, α-Al 2 O 3 films have been obtained on silicon substrates at 550 °C .…”

Section: Introductionmentioning

confidence: 99%

Low-Temperature Atomic Layer Deposition of α-Al₂O₃ Thin Films

Aarik

Mändar

Ritslaid

et al. 2021

Crystal Growth & Design

View full text Add to dashboard Cite

The atomic layer deposition of Al 2 O 3 films on Si(100) and α-Cr 2 O 3 was studied. The films were grown via AlCl 3 -H 2 O, AlCl 3 -O 3 , Al(CH 3 ) 3 -H 2 O, and Al(CH 3 ) 3 -O 3 processes at 300−750 °C. The films deposited from AlCl 3 and H 2 O at temperatures ≥ 400 °C on α-Cr 2 O 3 contained the corundum phase of alumina (α-Al 2 O 3 ). The densities and refractive indices of the α-Al 2 O 3 films were close to the corresponding values of single-crystal α-Al 2 O 3 and exceeded markedly those of amorphous Al 2 O 3 . The α-Al 2 O 3 phase was also obtained in the films deposited at 450 °C on α-Cr 2 O 3 from AlCl 3 and O 3 and from Al(CH 3 ) 3 and H 2 O. However, the crystallinity, densities, and refractive indices of the latter films were lower than those of the films deposited at 450 °C on α-Cr 2 O 3 from AlCl 3 and H 2 O. Etching in hot (110 °C) 80% H 2 SO 4 was used to characterize the chemical resistance of the films in aggressive environments. The etching rate of α-Al 2 O 3 deposited at 450−750 °C was more than 1000 times lower than that of predominantly amorphous Al 2 O 3 , and also lower than those of the films that were grown on Si(100) at 750 °C and contained γ-Al 2 O 3 , δ-Al 2 O 3 , and/or θ-Al 2 O 3 .

show abstract

The crystallographic template effect assisting the formation of stable α-Al2O3 during low temperature oxidation of Fe–Al alloys

Cited by 34 publications

References 45 publications

Laser-Induced Trapping of Metastable Amorphous AlO_x/C (2.5 < x ≤ 3.5) Nanocomposites: Implications for Use as Solid Phase Gas Generators

Laser-Induced Trapping of Metastable Amorphous AlO_x/C (2.5 < x ≤ 3.5) Nanocomposites: Implications for Use as Solid Phase Gas Generators

Metastable-Stable Phase Transformation Behavior of Al2O3 Scale Formed on Fe–Ni–Al Alloys

Low-Temperature Atomic Layer Deposition of α-Al₂O₃ Thin Films

Contact Info

Product

Resources

About

The crystallographic template effect assisting the formation of stable α-Al2O3 during low temperature oxidation of Fe–Al alloys

Cited by 34 publications

References 45 publications

Laser-Induced Trapping of Metastable Amorphous AlOx/C (2.5 < x ≤ 3.5) Nanocomposites: Implications for Use as Solid Phase Gas Generators

Laser-Induced Trapping of Metastable Amorphous AlOx/C (2.5 < x ≤ 3.5) Nanocomposites: Implications for Use as Solid Phase Gas Generators

Metastable-Stable Phase Transformation Behavior of Al2O3 Scale Formed on Fe–Ni–Al Alloys

Low-Temperature Atomic Layer Deposition of α-Al2O3 Thin Films

Contact Info

Product

Resources

About

Laser-Induced Trapping of Metastable Amorphous AlO_x/C (2.5 < x ≤ 3.5) Nanocomposites: Implications for Use as Solid Phase Gas Generators

Laser-Induced Trapping of Metastable Amorphous AlO_x/C (2.5 < x ≤ 3.5) Nanocomposites: Implications for Use as Solid Phase Gas Generators

Low-Temperature Atomic Layer Deposition of α-Al₂O₃ Thin Films