Size effect on thermodynamic properties of CaMoO4 micro/nano materials and reaction systems

CaMoO4 micro/nano hollow spheres with three different sizes were prepared via a reverse-microemulsion route at room temperature. Through designing a novel thermochemical cycle, the relationship between thermodynamic properties of nano CaMoO4 and bulk CaMoO4 was built. Combined with in situ microcalorimetry, change regularities for the thermodynamic properties of the prepared CaMoO4 micro/nano materials and reaction systems were obtained. The results reveal that size effect has significant influence on thermodynamic properties of micro/nano materials and reaction systems. Along with the size decreasing, the standard molar enthalpy, standard molar Gibbs free energy and standard molar entropy of reaction of micro/nano reaction systems decreased, but the standard molar enthalpy of formation, standard molar Gibbs free energy of formation and standard molar entropy of micro/nano materials increased. (c) 2012 Elsevier Masson SAS. All rights reserved.