Considerable effort has been exerted using theoretical calculations to determine solid surface energies. Nanomaterials with high surface energy depending on morphology and size exhibit enhanced reactivity. Thus, investigating the effects of morphology, size, and nanostructure on the surface energies and kinetics of nanomaterials is important. This study determined the surface energies of silver phosphate (Ag3PO4) micro-/nanocrystals and their kinetic parameters when reacting with HNO3by using microcalorimetry. This study also discussed rationally combined thermochemical cycle, transition state theory, basic theory of chemical thermodynamics with thermokinetic principle, morphology dependence of reaction kinetics, and surface thermodynamic properties. Results show that the molar surface enthalpy, molar surface entropy, molar surface Gibbs free energy, and molar surface energy of cubic Ag3PO4micro-/nanocrystals are larger than those of rhombic dodecahedral Ag3PO4micro-/nanocrystals. Compared with rhombic dodecahedral Ag3PO4, cubic Ag3PO4with high surface energy exhibits higher reaction rate and lower activation energy, activation Gibbs free energy, activation enthalpy, and activation entropy. These results indicate that cubic Ag3PO4micro-/nanocrystals can overcome small energy barrier faster than rhombic dodecahedral Ag3PO4micro-/nanocrystals and thus require lower activation energy.

Web-like ZnO nanostructures have been successfully synthesized using the potassium nitrate route at various temperatures to simplify conventional preparation methods. The structures and morphologies of the as-prepared products were characterized by X-ray powder diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM). The results showed that the reaction temperature was an important parameter, and that there was a feedback effect between nano-structure and growth parameters, combined with in situ micro-calorimetry, the reaction rate constants of the three systems were found to have been: 2.43×10 −6 , 2.70×10 −8 and 3.12×10 −7 s −1 respectively. Furthermore, based on the relationship governing the potential differences between nano-and bulk ZnO, thermodynamic functions of nano-ZnO such as standard molar entropy (m,ZnO(nano) S ), standard molar Gibbs free energy of formation (m,ZnO(nano) r G  ), and standard molar enthalpy of formation (r m,ZnO(nano) H  ) have been calculated by the electrochemical method. nano-thermodynamics, nano-ZnO, thermal properties, microcalorimetry, thermodynamic functions

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