Surface water and the origin of the positive excess specific heat for 7 nm rutile and anatase nanoparticles

被引：68

作者：

Boerio-Goates, J ^{[1
]}

Li, GS ^{[1
]}

Li, LP ^{[1
]}

Walker, TF ^{[1
]}

Parry, T ^{[1
]}

Woodfield, BF ^{[1
]}

机构：

[1] Brigham Young Univ, Dept Chem & Biochem, Provo, UT 84602 USA

来源：

NANO LETTERS | 2006年 / 6卷 / 04期

关键词：

D O I：

10.1021/nl0600169

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Specific heats (15-350 K) have been measured on 7 nm TiO2 anatase and rutile nanoparticles containing significant amounts of surface-adsorbed water. By successively reducing the water content without changing particle size, we observed two types of water behavior. The specific heat of bare 7 nm particles was estimated using the water specific heats. Contrary to previous literature reports, the bare small particle specific heats are the same as those of the bulk, within experimental error.

引用

页码：750 / 754

页数：5

共 20 条

[1] ON THE HEAT CAPACITY OF CRYSTALLINE MAGNESIUM OXIDE [J].

BARRON, THK ;

BERG, WT ;

MORRISON, JA .

PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL AND PHYSICAL SCIENCES, 1959, 250 (1260) :70-83

[2] SPECIFIC-HEAT STUDY OF NANOCRYSTALLINE PALLADIUM [J].

CHEN, YY ;

YAO, YD ;

HSIAO, SS ;

JEN, SU ;

LIN, BT ;

LIN, HM ;

TUNG, CY .

PHYSICAL REVIEW B, 1995, 52 (13) :9364-9369

[3]

GARVIN, 1987, CODATA THERMODYNAMIC

[4] Evidence of linear lattice expansion and covalency enhancement in rutile TiO2 nanocrystals [J].

Li, GS ;

Boerio-Goates, J ;

Woodfield, BF ;

Li, LP .

APPLIED PHYSICS LETTERS, 2004, 85 (11) :2059-2061

[5]

Li GS, 2003, J MATER RES, V18, P2664

[6] High purity anatase TiO2 nanocrystals:: Near room-temperature synthesis, grain growth kinetics, and surface hydration chemistry [J].

Li, GS ;

Li, LP ;

Boerio-Goates, J ;

Woodfield, BF .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2005, 127 (24) :8659-8666

[7] High-resolution neutron-scattering study of slow dynamics of surface water molecules in zirconium oxide [J].

Mamontov, E .

JOURNAL OF CHEMICAL PHYSICS, 2005, 123 (02)

[8] Observation of fragile-to-strong liquid transition in surface water in CeO2 -: art. no. 171101 [J].

Mamontov, E .

JOURNAL OF CHEMICAL PHYSICS, 2005, 123 (17)

[9] Surface energies and thermodynamic phase stability in nanocrystalline aluminas [J].

McHale, JM ;

Auroux, A ;

Perrotta, AJ ;

Navrotsky, A .

SCIENCE, 1997, 277 (5327) :788-791

[10] Thermodynamics of ice polymorphs and 'ice-like' water in hydrates and hydroxides [J].

Mercury, L ;

Vieillard, P ;

Tardy, Y .

APPLIED GEOCHEMISTRY, 2001, 16 (02) :161-181

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