Preparation Of Photocatalysts Based On Porous Ceramic And Their Photocatalytic Performances Study

The photocatalytic technology has been considered as one of the most promising techniques for environmental elimination in the twenty-first century,due to its outstanding characteristics such as ease of operation,mild reaction conditions and no secondary pollution.It is necessary to develop new energy sources,due to low energy consumption.By utilizing two kinds of porous ceramic materials as catalyst substrates,different supported photocatalysts were obtained.Photocatalytic degradation experiments of methyl orange,acid red 18 and rhodamine B simulation were investigeted.The main research contents and conclusions of this work are summarized as follows:1.A novel photocatalyst(PAOG/AgNPs-Hemin)based on Al2O3 porous ceramic was synthesized via photochemical reduction-deposition,self-assembly and coordination bonds.Based on the analysis of SEM,HRTEM and mapping images,the structures of Al2O3 porous ceramic and the crystallinity of the silver particles were clarified.Furthermore,the successful preparation of PAOG/AgNPs-Hemin composite was confirmed via the analysis of SEM,XPS,UV-vis and FTIR.2.The photocatalytic degradation experiments were conducted by degradation of MO and acid red 18 under visible light or UV irradiation.PAOG/AgNPs-Hemin exhibited enhanced degradation activity compared with PAOG/Hemin.The PAOG/AgNPs-Hemin photocatalyst showed the higher photocatalytic activity under UV irradiation than under visible light.The degradation efficiencies of MO decrease with pH increased in reactions.Interestingly,the best photocatalytic activity of PAOG/AgNPs-Hemin photocatalyst occurred at pH 1.And the reproducibility of PAOG/AgNPs-Hemin photocatalyst was very well.3.TiO2 porous ceramic was prepared in a sintering process.Meantime,TiO2 porous ceramic/Ag-AgCl composite was prepared via methods of deposition and photochemical reduction.The X ray diffraction(XRD),UV-vis diffuse reflectance spectra(UV-vis),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX)and X ray photoelectron spectroscopy(XPS)technique were utilized to characterize the photocatalyst.It was clearly observed that the average size of Ag-AgCl nanoparticles is about 300 nm and regular(cube-like).4.We explored the photocatalytic degradation effects of MO and RhB under visible light irradiation.The influence of reduction time on the photocatalytic activity was analyzed.The reproducibility of TiO2 porous ceramic/Ag-AgCl photocatalyst was still good after four times cyclic experiments.At the same,it is a new kind of photocatalytic material with good performances.