Role of cohesive energy on the interparticle coalescence behavior of dispersed nanoparticles subjected to energetic ion irradiation

The present work reports on the conditions of nanoparticle growth and splitting under energetic ion irradiation. Cohesive energy that determines the thermal stability of a given nanoparticle system was calculated by extending surface area difference (SAD) and liquid drop model (LDM). Based on the size-dependent cohesive energy calculations, the interparticle coalescence mechanism is discussed for a ZnS-based nanoparticle system with special reference to a variety of matrices. The interparticle separation is found to play key role in particle–particle coalescence leading to nanoparticle growth or partial evaporation that results in splitting.

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Structural relationships in the synthesis of cubic boron nitride thin films by ion-assisted deposition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017092x ◽

1994 ◽

Vol 52 ◽

pp. 638-639

Author(s):

D. L. Medlin ◽

T. A. Friedmann ◽

P. B. Mirkarimi ◽

M. J. Mills ◽

K. F. McCarty

Keyword(s):

Boron Nitride ◽

Ion Irradiation ◽

Cubic Boron Nitride ◽

Film Stress ◽

Bonded Phases ◽

Structural Relationships ◽

Precursor Material ◽

Pressure Synthesis ◽

Microstructure Of The Material

The allotropes of boron nitride include two sp2-bonded phases with hexagonal and rhombohedral structures (hBN and rBN) and two sp3-bonded phases with cubic (zincblende) and hexagonal (wurtzitic) structures (cBN and wBN) (Fig. 1). Although cBN is synthesized in bulk form by conversion of hBN at high temperatures and pressures, low-pressure synthesis of cBN as a thin film is more difficult and succeeds only when the growing film is simultaneously irradiated with a high flux of ions. Only sp2-bonded material, which generally has a disordered, turbostratic microstructure (tBN), will form in the absence of ion-irradiation. The mechanistic role of the irradiation is not well understood, but recent work suggests that ion-induced compressive film stress may induce the transformation to cBN.Typically, BN films are deposited at temperatures less than 1000°C, a regime for which the structure of the sp2-bonded precursor material dictates the phase and microstructure of the material that forms from conventional (bulk) high pressure treatment.

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The role of the substrate on the mechanical and thermal stability of Pd thin films during hydrogen (de)sorption

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2020.10.163 ◽

2021 ◽

Vol 46 (5) ◽

pp. 4137-4153

Author(s):

Neha Verma ◽

Rob Delhez ◽

Niek M. van der Pers ◽

Frans D. Tichelaar ◽

Amarante J. Böttger

Keyword(s):

Thin Films ◽

Thermal Stability ◽

Thermal Stability Of

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Mossbauer Study of the Role of Aluminum and Chromium in Nitrogen Implanted Iron

MRS Proceedings ◽

10.1557/proc-235-509 ◽

1991 ◽

Vol 235 ◽

Cited By ~ 2

Author(s):

M. Kopcewicz ◽

J. Jagielski ◽

A. Turos ◽

D. L. Williamson

Keyword(s):

Thermal Stability ◽

Ion Implantation ◽

Metallic Iron ◽

Conversion Electron ◽

Alloying Elements ◽

Mössbauer Study ◽

Conversion Electron Mössbauer Spectroscopy ◽

Conversion Electron Mossbauer Spectroscopy ◽

Thermal Stability Of

ABSTRACTThe role of alloying elements such as Cr and Al in the formation and stability of the nitride phases formed due to N ion implantation into metallic iron was studied by conversion electron Mössbauer spectroscopy (CEMS). The thermal stability of nitride phases upon 1 h annealing was greatly increased as a result of co-implanting either Cr or Al with N as compared to pure α-Fe implanted only with N.

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