Atomic origin of the morphological evolution of aluminum hydride (AlH3) nanoparticles during oxidation using reactive force field simulations

Song, Lina; Zhao, Fengqi; Xu, Shidang; Ju, Xue‐Hai

doi:10.1016/j.apsusc.2020.146249

Cited by 26 publications

(7 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To have random distribution, an even higher temperature is needed. However, in the ignition or combustion simulations using RMD methods, such configurations of N and O adsorbates were not reproduced. , When considering the top few Al layers adsorbed or intercalated with these atoms, their aggregation needs even higher temperatures to break. The inward diffusion kinetics would be very different for adatoms at periphery and core of the island, not to mention the isolated ones.…”

Section: Resultsmentioning

confidence: 99%

NO_x on Al: The Unusual Adsorption Site Preference and the Attraction among Adsorbates

Hai

Ding

2022

J. Phys. Chem. C

View full text Add to dashboard Cite

The interactions between NO x , N and O atoms, and aluminum (Al) surfaces including crystal planes and nanoparticles (ANPs) are systematically investigated by using density functional theory (DFT) calculations, canonical Monte Carlo (CMC) simulations, and reactive molecular dynamics (RMD) simulations. NO x has two adsorption states (molecular and dissociated) on the Al surfaces, which are separated by a low energy barrier. The adsorption of NO x in either state does not favor Al nanoparticles (ANPs), opposite to its behavior on transition metals. In addition, NO x does not show preference toward smaller ANPs or their vertices or edges; instead, it prefers threefold sites that resemble the fcc or hcp sites on a (111) surface. The big deformation energy of ANPs is found to be the reason. The N* adatoms are most stable at the tetrahedron interstitial sites between the surface and the first sublayer, where an aluminum nitride (AlN)-like structure is formed. Similar to O* adatoms on Al, the isotropic attraction between N* adatoms has a significant influence on their diffusion, both in-plane and in cross-layer. Besides, the attraction within a N−O pair as the first nearest neighbors (1NN) is roughly twice that of their respective attraction (about 0.1 eV/O−O or N−N). However, RMD simulations ignore the attraction among the N* adatoms as well as between the N* and O* adatoms, though O−O attractions are somehow incorporated. CMC simulations prove that the attraction still governs the configuration of the adatoms at 600 K with all adatoms congregating into a single polygonal island, and it is still influential even when reaching 1500 K. In addition, the fragmented products (Al x N y ) of Al combustion in NO x according to DFT feature the tetra-coordinated Al centered inside the tetrahedron of four N atoms, different from the pyramidal unit structure with Al as the vertex by RMD simulations. Our results demonstrate that the unusual behaviors of NO x including the dissociated atoms on Al are caused by both the softness (low Young's modulus) of Al and the attractions among adsorbates, which have important implications for understanding the behaviors of gas molecules on main group metals in general.

show abstract

Section: Resultsmentioning

confidence: 99%

NO_x on Al: The Unusual Adsorption Site Preference and the Attraction among Adsorbates

Hai

Ding

2022

J. Phys. Chem. C

View full text Add to dashboard Cite

show abstract

“…We used the number of Cu–O bonds to describe the oxidation state of Cu equivalently. It is considered to be an accurate method that is used in many research studies. ,,, The Cu i + is used as a symbol to distinguish the structures of different number of O atoms bonded to Cu atoms, in which Cu 0+ , Cu 1+ , Cu 2+ , Cu 3+ , and Cu 4+ represent zero, one, two, three, and four O atoms bonded with one Cu atom. We show the stable structures of all Cu i + except Cu 1+ (as already shown in Figure S2) in Figure S3.…”

Section: Resultsmentioning

confidence: 99%

Structural Transformation from Low-Coordinated Oxides to High-Coordinated Oxides during the Oxidation of Cu Nanoparticles

Zhang

Zheng

et al. 2021

J. Phys. Chem. C

View full text Add to dashboard Cite

Comprehensively understanding the oxidation mechanism of copper nanoparticles (NPs) is valuable to the corrosion protection of metals and controllable preparation of Cu oxide nanoparticles. In this work, we performed reactive molecular dynamics simulations to study the oxidation behaviors of Cu NPs. Results show that Cu NP oxidation is an expanding process from the surface oxidation nuclei to their surroundings, forming an oxide film and finally growing inward. In the process of oxide film formation, the oxide changes from a low-coordination structure to a high-coordination structure. Besides, the influences of oxygen content and temperature on the oxidation process have also been discussed. Excess oxygen contents at low temperature may have less effect on the oxidation, while the temperature rise can effectively promote oxidation and growth of high-coordinated oxides. This work provides a better understanding of the atomic-scale oxidation mechanism of Cu NPs, which is helpful to design and prepare the highly active, controllable, and stable Cu NPs.

show abstract

“…Metals, especially aluminum, have high combustion enthalpy, which can increase the combustion temperature of the system, and aluminum combustion products are harmless and low cost, so they are widely used as fuel additives. An in-depth understanding of the pyrolysis or combustion of aluminum itself, [122][123][124][125][126][127][128][129] energetic materials/aluminum composites 112,[130][131][132][133][134][135] and small molecule/aluminum systems 123,134,[136][137][138][139][140] is of great interest.…”

Section: Pyrolysis and Combustion Mechanism Of Cl-20mentioning

confidence: 99%

“…This study reveals the complex interaction between oxidants and ANPs, which provides guidance for the proportion design of different oxidants in the presence of ANPs. Song et al 128 studied the morphology evolution of aluminum hydride nanoparticles (AHNPs) during dehydrogenation and oxidation. They used a time step of 0.1 fs in the simulation.…”

Section: 221mentioning

confidence: 99%

Recent ReaxFF MD studies on pyrolysis and combustion mechanisms of aviation/aerospace fuels and energetic additives

Chen

Li²,

Zhang

et al. 2023

Energy Adv.

View full text Add to dashboard Cite

show abstract

Atomic origin of the morphological evolution of aluminum hydride (AlH3) nanoparticles during oxidation using reactive force field simulations

Cited by 26 publications

References 47 publications

NO_x on Al: The Unusual Adsorption Site Preference and the Attraction among Adsorbates

NO_x on Al: The Unusual Adsorption Site Preference and the Attraction among Adsorbates

Structural Transformation from Low-Coordinated Oxides to High-Coordinated Oxides during the Oxidation of Cu Nanoparticles

Recent ReaxFF MD studies on pyrolysis and combustion mechanisms of aviation/aerospace fuels and energetic additives

Contact Info

Product

Resources

About

Atomic origin of the morphological evolution of aluminum hydride (AlH3) nanoparticles during oxidation using reactive force field simulations

Cited by 26 publications

References 47 publications

NOx on Al: The Unusual Adsorption Site Preference and the Attraction among Adsorbates

NOx on Al: The Unusual Adsorption Site Preference and the Attraction among Adsorbates

Structural Transformation from Low-Coordinated Oxides to High-Coordinated Oxides during the Oxidation of Cu Nanoparticles

Recent ReaxFF MD studies on pyrolysis and combustion mechanisms of aviation/aerospace fuels and energetic additives

Contact Info

Product

Resources

About

NO_x on Al: The Unusual Adsorption Site Preference and the Attraction among Adsorbates

NO_x on Al: The Unusual Adsorption Site Preference and the Attraction among Adsorbates