TY - JOUR
T1 - Calorimetry of nanoparticles, surfaces, interfaces, thin films, and multilayers
AU - Navrotsky, Alexandra
N1 - Funding Information:
I have to thank a large number of people. Some of them are in the audience here. Indeed, without our group and its enthusiasm and its hard work, obviously there would be much less science done. So, thank you all, Thermochemistry. I also thank the National Science Foundation, the Department of Energy, and my three universities (Arizona State, Princeton, and UC Davis) for continued and virtually continuous support.
PY - 2007/1
Y1 - 2007/1
N2 - Calorimetry gives insight into the stability of nanophase materials. Using TiO2 as an example, the interplay of energetics of polymorphism, surface energy, and surface hydration is discussed. Oxide melt solution calorimetry, water adsorption calorimetry, and adiabatic heat capacity studies together show the following. The metastability of bulk polymorphs increases in the order rutile, brookite, anatase, while the surface energy increases in the opposite order. This leads to crossovers in phase stability at the nanoscale, which appears to be a general phenomenon. Hydration plays a major role in stabilizing nanoparticles and the first layers of water are tightly bound. There is little excess heat capacity and no significant excess vibrational entropy in nanophase rutile or anatase. Further applications of calorimetry to thin films, interfaces, multilayers, and sub-milligram samples are presented.
AB - Calorimetry gives insight into the stability of nanophase materials. Using TiO2 as an example, the interplay of energetics of polymorphism, surface energy, and surface hydration is discussed. Oxide melt solution calorimetry, water adsorption calorimetry, and adiabatic heat capacity studies together show the following. The metastability of bulk polymorphs increases in the order rutile, brookite, anatase, while the surface energy increases in the opposite order. This leads to crossovers in phase stability at the nanoscale, which appears to be a general phenomenon. Hydration plays a major role in stabilizing nanoparticles and the first layers of water are tightly bound. There is little excess heat capacity and no significant excess vibrational entropy in nanophase rutile or anatase. Further applications of calorimetry to thin films, interfaces, multilayers, and sub-milligram samples are presented.
KW - Calorimetry
KW - Hydration
KW - Nanoparticles
KW - Surface energy
KW - Titania polymorphs
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U2 - 10.1016/j.jct.2006.09.011
DO - 10.1016/j.jct.2006.09.011
M3 - Article
AN - SCOPUS:33846283744
SN - 0021-9614
VL - 39
SP - 1
EP - 9
JO - Journal of Chemical Thermodynamics
JF - Journal of Chemical Thermodynamics
IS - 1
ER -