Hydrothermal Synthesis on Biocl.BiOI Compound Semiconductor and Its Photocatalytic Properties
|School||Harbin Institute of Technology|
|Course||Physical and chemical|
|Keywords||Photocatalytic Hydrothermal method Degradation of Dyes Compound Semiconductor BiOCl / BiOI BiOI/Bi5O7I|
The Biox (Cl, Br, I) photocatalysts because of its unique electronic structure and band structure, performance superior to other types of semiconductor photocatalytic degradation of performance in the photocatalytic degradation of organic dyes. BiOX (Cl, Br, I) in the same organic dye degradation but separate BiOX (Cl, Br, I) activity in the degradation of the organic dye is low, while the type of activity are also different. Therefore, this thesis by hydrothermal method or water bath method synthesized BiOI / the Bi 5 the O 7 I BiOCl / BiOI the BiOI / BiOBr compound semiconductor photocatalyst by XRD , BET, UV-Vis, SEM, TEM, PL and other means of the phase structure of the synthesized samples, specific surface area, band structure, surface morphology, and photocatalytic degradation of organic dyes were studied. Bi (NO 3 ) 3 , KI and ammonia as the starting material by step hydrothermal the synthesis BiOI / the Bi 5 O < sub> 7 I catalyst. XRD analysis indicated that, pH = 7, the synthesized samples for BiOI pure phase, but when the pH = 9, Bi 5 O 7 I diffraction peak, when the pH = 11, has generated most of the Bi 5 the O 7 I. Therefore, by controlling the pH to generate the catalyst composite of the two substances. Secondly, through the control of Bi: the proportion of I can to control BiOI and Bi , 5 the O 7 I content in the mixture. The photocatalytic test results showed that the catalyst containing the two substances in the product than a single catalyst degrading activity. Bi (NO 3 ) 3 , KI, and NaCl as the starting material, the use of two-step Hydrothermal Synthesis BiOCl / BiOI compound semiconductor photocatalyst. The first step hydrothermal first synthetic monomer BiOI of the second step hydrothermal synthesis of compound semiconductor photocatalyst BiOCl / BiOI. XRD results show that the catalyst samples prepared by the hydrothermal method the diffraction peaks containing BiOI containing BiOCl diffraction peaks of the two-phase coexistence. BiOCl / BiOI compound semiconductor SEM results hydrothermal synthesis of BiOI round sheet structure with good distribution, and synthetic BiOCl monomer flower globular structure. BiOCl / BiOI compound semiconductor catalyst flakes and flowers mixed spherical morphology. Finally, the systematic study of the photocatalytic activity of the compound semiconductor prepared under hydrothermal conditions. The results showed that 20% BiOCl / BiOI activity in the degradation of methyl orange (MO) best and 70% BiOCl / BiOI Degradation of Rhodamine B (RhB) activity best catalyst degradation due to two different dye, according to a series of experiments the same system with a different mechanism of photocatalytic degradation. Bi (NO 3 ) 3 , KI, and NaBr as a starting material, a one-step water bath prepared BiOI the / BiOBr compound semiconductor photocatalyst. The compound semiconductor SEM photos for the BiOI / BiOBr results showed that the synthesized samples of the water bath method for the irregular curved flower sheet-like structure, the type of sheet-like structure while the monomer synthesized under the same conditions BiOI and BiOBr.