采用室温反相微乳液法制备了3种不同尺寸的花生状微/纳米 CaMoO4.基于纳米 CaMoO4与块体CaMoO4热力学性质的本质差异,结合化学热力学基本理论及热动力学原理,推导出纳米CaMoO4摩尔表面热力学函数的关系式.在此基础上,采用原位微量热技术获得了花生状微/纳米CaMoO4的摩尔表面热力学函数.结果表明,花生状微/纳米CaMoO4的表面热力学性质变化具有尺寸效应,即随着尺寸的减小,摩尔表面焓、摩尔表面Gibbs自由能、摩尔表面熵均增加.
Mirco/nano peanut-shaped CaMoO4 with three different sizes were prepared via reverse-microemul-sion method at room temperature. Based on the essential difference between thermodynamic properties of nano CaMoO4 and bulk CaMoO4 , the equations for acquiring molar surface thermodynamic functions of nano CaMoO4 were derived via combining the basic theory of chemical thermodynamics with thermokinetic principle. According to the derived equations, molar surface thermodynamic functions such as molar surface enthalpy, molar surface Gibbs free energy and molar surface entropy of the synthesized peanut-like mirco/nano CaMoO4 were successfully gained by in situ microcalorimetry. The results demonstrated that the size has significant in-fluence on surface thermodynamic properties. Along with the size reducing, the molar surface enthalpy, molar surface Gibbs free energy and molar surface entropy increased.