A model for the behavior of an isolated TiO2 nanoparticle under extreme conditions

被引：3

作者：

Lowther, J. E.

机构：

[1] Univ Witwatersrand, NRF Ctr Excellence Strong Mat, DST, ZA-2050 Johannesburg, South Africa

[2] Univ Witwatersrand, Sch Phys, ZA-2050 Johannesburg, South Africa

来源：

HIGH PRESSURE RESEARCH | 2006年 / 26卷 / 02期

关键词：

nanoparticle; anatase; high pressure; modeling;

D O I：

10.1080/08957950600764288

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Molecular dynamics simulations have been used to model the behavior of a 4 nm size particle of anatase TiO2 when placed under pressure. The model suggests that disorder is initiated in a surface crust of the particles with some crystallinity being retained in the core. The surface disorder increases with increasing pressure. Volume changes deduced under pressure are used in a conventional equation of state model from which a bulk modulus is deduced and found to have a value enhanced over the crystalline value.

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页码：131 / 135

页数：5

相关论文

共 16 条

[1] High-pressure structural phase transitions in TiO2 and synthesis of the hardest known oxide [J].

Ahuja, R ;

Dubrovinsky, LS .

JOURNAL OF PHYSICS-CONDENSED MATTER, 2002, 14 (44) :10995-10999

[2] Solid-state dye-sensitized mesoporous TiO2 solar cells with high photon-to-electron conversion efficiencies [J].

Bach, U ;

Lupo, D ;

Comte, P ;

Moser, JE ;

Weissörtel, F ;

Salbeck, J ;

Spreitzer, H ;

Grätzel, M .

NATURE, 1998, 395 (6702) :583-585

[3] Derivation of force field parameters for TiO2-H2O systems from a initio calculations [J].

Bandura, AV ;

Kubicki, JD .

JOURNAL OF PHYSICAL CHEMISTRY B, 2003, 107 (40) :11072-11081

[4]

BANFIELD JF, 2001, REV MINERALOGY GEOCH

[5]

Chen B, 2002, PHYS REV B, V66, DOI 10.1103/PhysRevB.66.144101

[6] Intrinsic ferromagnetism in insulating cobalt doped anatase TiO2 -: art. no. 157204 [J].

Griffin, KA ;

Pakhomov, AB ;

Wang, CM ;

Heald, SM ;

Krishnan, KM .

PHYSICAL REVIEW LETTERS, 2005, 94 (15)

[7] Effect of grain size on structural transitions in anatase TiO2:: A Raman spectroscopy study at high pressure -: art. no. 134102 [J].

Hearne, GR ;

Zhao, J ;

Dawe, AM ;

Pischedda, V ;

Maaza, M ;

Nieuwoudt, MK ;

Kibasomba, P ;

Nemraoui, O ;

Comins, JD ;

Witcomb, MJ .

PHYSICAL REVIEW B, 2004, 70 (13) :134102-1

[8] Ultrastability and enhanced stiffness of ∼6 nm TiO2 nanoanatase and eventual pressure-induced disorder on the nanometer scale -: art. no. 035509 [J].

Pischedda, V ;

Hearne, GR ;

Dawe, AM ;

Lowther, JE .

PHYSICAL REVIEW LETTERS, 2006, 96 (03)

[9] Softening of nanocrystalline metals at very small grain sizes [J].

Schiotz, J ;

Di Tolla, FD ;

Jacobsen, KW .

NATURE, 1998, 391 (6667) :561-563

[10] DL_POLY_2.0: A general-purpose parallel molecular dynamics simulation package [J].

Smith, W ;

Forester, TR .

JOURNAL OF MOLECULAR GRAPHICS, 1996, 14 (03) :136-141