Controllable Synthesis, In-Situ Growth,Thermodynamic And Kinetic Properties Of Calcium Molybdate Nanomaterials

Among the molybdates, calcium molybdate with a scheelite structure has the strongest luminous intensity at room temperature. Additionally, it has also presented a great application potential in scintillation crystal, microwave device, catalyst, energy storage, etc. Nanomaterials, due to its distinct basic effects, possess unique properties than traditional materials, and its preparation and properties studies have aroused worldwide attention and interest. Thermodynamic and kinetic properties are both of inherent attributes of materials, but, however, the related researches focused on nanomaterials are very inadequate.In this paper, various morphologies and different sizes of nano CaMoO4were controllably synthesized by liquid-phase route, and in-situ growth process of nano CaMoO4were studied by microcalorimetry. Based on the prepared products, the thermodynamic and kinetic properties of different reaction systems of nano CaMoO4were investigated, and the thermodynamic functions of nano CaMoO4were acquired.The main contents of this paper are as follows:1. Various morphologies and different sizes of nano CaMoO4like nanorods, nanowheats, nanospindles, nanopeanuts and nanospheres were prepared by a reverse microemulsion route at room temperature. And the influences of different growth factors such as oil-water proportion, ions concentration ratio, water phase concentration, etc. on morphology and size of the prepared products were discussed.2. In-situ growth of CaMo04nanocakes was investigated by RD496-â…¢ microcalorimeter. The thermodynamic and kinetic information of its nonequilibrium growth process was obtained, and the growth mechanism was interpreted. 3. The thermodynamic and kinetic properties of the reaction systems consisted of nano CaMoO4with various morphologies and different sizes and HCl solution were studied by microcalorimetry. And the change regularities of thermodynamic and kinetic parameters along with reaction temperature, morphologies and sizes of the reactants were discussed.4. Through designing a thermochemical cycle and combining with thermokinetic theory and transition state theory, thermodynamic functions of the prepared nano CaMoO4were achieved by microcalorimetry. And the evolution rules of the thermodynamic functions along with size and morphology were inquired.