Modelling the size effect on the melting temperature of nanoparticles, nanowires and nanofilms

Safaei, Ali; Shandiz, M. Attarian; Sanjabi, S.; Barber, Z. H.

doi:10.1088/0953-8984/19/21/216216

Cited by 76 publications

(91 citation statements)

References 25 publications

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“…3 Further studies were performed by a great number of researchers. [4][5][6][7][8][9][10][11][12] The results reveal that isolated nanoparticles and substrate-supported nanoparticles with relatively free surfaces usually exhibit a significant decrease in melting temperature as compared with the corresponding conventional bulk materials. The physical origin for this phenomenon is that the ratio of the number of surface-to-volume atoms is enormous, and the liquid/vapor interface energy is generally lower than the average solid/vapor interface energy.…”

Section: Thermodynamic Properties Of Silver Nanoparticlesmentioning

confidence: 99%

“…A lot of thermodynamic models of nanoparticles melting assume spherical particles with homogeneous surfaces and yield a linear or almost linear decreasing melting point with increasing the inverse of the cluster diameter. 2,6,[10][11][12] However, the determination of some parameters in these models is difficult or arbitrary. Actually, the melting-phase transition is one of the most fundamental physical processes.…”

Section: Thermodynamic Properties Of Silver Nanoparticlesmentioning

confidence: 99%

See 1 more Smart Citation

Thermodynamic Properties of Nano-Silver and Alloy Particles

Hu¹,

Xiao²,

Deng³

et al. 2010

Silver Nanoparticles

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In this chapter, the analytical embedded atom method and calculating Gibbs free energy method are introduced briefly. Combining these methods with molecular dynamic and Monte Carlo techniques, thermodynamics of nano-silver and alloy particles have been studied systematically. For silver nanoparticles, calculations for melting temperature, molar heat of fusion, molar entropy of fusion, and temperature dependences of entropy and specific heat capacity indicate that these thermodynamic properties can be divided into two parts: bulk quantity and surface quantity, and surface atoms are dominant for the size effect on the thermodynamic properties of nanoparticles. Isothermal grain growth behaviors of nanocrystalline Ag shows that the small grain size and high temperature accelerate the grain growth. The grain growth processes of nanocrystalline Ag are well characterized by a power-law growth curve, followed by a linear relaxation stage. Beside grain boundary migration and grain rotation mechanisms, the dislocations serve as the intermediate role in the grain growth process. The isothermal melting in nanocrystalline Ag and crystallization from supercooled liquid indicate that melting at a fixed temperature in nanocrystalline materials is a continuous process, which originates from the grain boundary network. The crystallization from supercooled liquid is characterized by three characteristic stages: nucleation, rapid growth of nucleus, and slow structural relaxation. The homogeneous nucleation occurs at a larger supercooling temperature, which has an important effect on the process of crystallization and the subsequent crystalline texture. The kinetics of transition from liquid to solid is well described by the Johnson-Mehl-Avrami equation. By extrapolating the mean grain size of nanocrystal to an infinitesimal value, we have obtained amorphous model from Voronoi construction. From nanocrystal to amorphous state, the curve of melting temperature exhibits three characteristic regions. As mean grain size above about 3.8 nm for Ag, the melting temperatures decrease linearly with the reciprocal of grain size. With further decreasing grain size, the melting temperatures almost keep a constant. This is because the dominant factor on melting temperature of nanocrystal shifts from grain phase to grain boundary one. As a result of fundamental difference in structure, the amorphous has a much lower solid-to-liquid transformation temperature than that of nanocrystal.

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Section: Thermodynamic Properties Of Silver Nanoparticlesmentioning

confidence: 99%

Section: Thermodynamic Properties Of Silver Nanoparticlesmentioning

confidence: 99%

Thermodynamic Properties of Nano-Silver and Alloy Particles

Hu¹,

Xiao²,

Deng³

et al. 2010

Silver Nanoparticles

View full text Add to dashboard Cite

show abstract

“…These yield a linear or almost linear decreasing melting point with increasing the inverse of the cluster diameter [88,[90][91][92]. By dissolving the bulk silver in a sample solution, an equilibrium forms between the crystal and liquid phases of silver clusters, at a certain temperature at which the Gibbs free energies of these two phases become the same.…”

Section: Thermodynamics Of Agnps In Aqueous Mediummentioning

confidence: 99%

Mechanism and behavior of silver nanoparticles in aqueous medium as adsorbent

Dastafkan

Khajeh

Bohlooli

et al. 2015

Talanta

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“…The melting temperature and the cohesive energy change linearly. Many researchers (Safai et al,2007, Qi & Wang 2004a, Qi 2005, Jiang et al, 2000b, Zhang et al, 2000 successfully modelled and predicted the melting temperature of some nanomaterials. Other researchers, found quite a distinct structure properties between nanoparticles and nanostructured materials (Y. F. .…”

Section: Introductionmentioning

confidence: 99%