Photocatalytic Performance Of Perovskite ABF₃ Fluorides

Pervoskite-type composite Fluoride ABF₃ were prepared by reflux method.The contrast of XRD spectra in different time determines the reaction time to be 5h.The Perovskite-type structure are determined by the XRD spectra.Through TEM analysis to prove that are nano-crystal structure.While refire the products preparated by reflux method,the particles back to a more decentralized and more conducive to the photocatalytic reaction.Using a fluorescent Hg lamp as irradiator,the degradation experiments of various water-soluble dyes were carried out in the suspension system of ABF₃ and carries on the attribute by the dye percent of decolorization to the series sample's photochemical catalysis activeness.Then using TEM,IR,UV-Vis and so on to analyze the catalyst photochemical catalysis active mechanism and the influencing factor emphatically.Conclusions are drawn as follows:While the samples are refire,the particles back to a more decentralized and photocatalytic capacity are enhenced. Because ofχ_AR(Na)＞χ_AR(K),so photocatalytic activity NaBF₃＞KBF₃;In the main group,atomic number of B is,the ionic radius reduced,negative increase,the ABF₃ perovskite structure to be more stable and have higher-acticity;Adsorption force of surface adsorbed oxygen is moderate to a more effective play Catalysis;study the sample's crystal structure shows that Perovskite-type＞non-Perovskite-type and Jane-Teller crystal structure＞Orthorhombic structure＞Cubic crystal structure Moreover the photochemical catalysis rule is many kinds of factor combined action result,therefore it is not compound linear law.In addition,we explore the reaction schemes and synthesis mechanism of the perovskite fluoride.The reflux method has many vitures such as simple technology, mild conditions and fast phase-transformation.Furthermore,by controlling conditions of crystal growth spherical.Reflux belongs to wet chemical.Through the conductivity measurement,XRD and the infrared spectrogram contrast obtains the possible mechanism.It shows that the pross is ion reaction,the solvent is to provide plasma environment and the necessary heat to the response.This principle has very important significance for extended the reflux method.