| Pollution abatement using semiconductor materials as photocatalysts under sunlight has been a subject of great interest. Photocatalytic degradation experiments of water-soluble dyes including Supramine red 3B, Procion brilliant orange Ⅱ, Nylomine blue 2Br and Cibacron brilliant blue KGL together with phenol in the suspension systems of nano-perovskite type ABO3 oxides were carried out in the paper. Photocatalytic oxidation activity of nano-perovskite type ABO3 oxides, their replaced compounds in A-site or B-site and partly doped complex was made a systemic study. Meanwhile, photocatalytic reduction of CO32- were carried out in order to decide photocatalytic reduction property. It is found that CO32- can be reduced into basic organic materials such as formaldehyde, methyl alcohol and formic acid, et al. Perovskite oxides are excellent candidates as photocatalysts particularly suited for pollution abatement and materialization of CO2. Here, a new field is found by using solar energy.At first, nano-perovskite type ABO3 oxides were synthesized by different methods of preparation including oxide sintering process, co-depositon process, sol-gel process and citric acid complex method. The results show sol-gel process and citric acid complex method are effective ways to prepare nano particles. By XRD and TEM technology analysis it is found that the particle size of prepared samples is 20～60nm, belongs to nano-particles.The effects of B ion radius, electron configuration, eletronegativity on the photocatalytic oxidation activity of nano-perovskite type ABO3 oxides were studied. In LaBO3(La=Cr,Mn,Fe,Co) compounds, binding energy of B-O decreases with decrease of B ion radius and increase of tolerance factor (t), which results in enhancement of photocatalytic oxidation activity nano-perovskite type ABO3 oxides. The order of photocatalytic oxidation activity is LaCrO3 photocatalytic oxidation activity enhances. A ion radius, electron configuration, eletronegativity are also important influence factors of photocatalytic oxidation activity of nano-perovskite type ABO3 oxides. Photocatalytic oxidation activity of ATiO3(A=La,Ca,Cd,Pb)increase with increase of Allred-Rochow eletronegativity of A element. By study of photocatalytic oxidation activity of AFeO3(A=La,Sr), it is found that two kinds of oxygen exist in both LaFeO3 and SrFeO3, that is crystal oxygen and adsorbed oxygen, adsorbed oxygen is active oxygen which can inhibit complex of e--h+ and produce highly reactive HO·. According to the results of XPS analysis, content of adsorbed oxygen in SrFeO3 is higher than in LaFeO3 leading to photocatalytic oxidation activity of SrFeO3 is higher than LaFeO3. In the meanwhile, a series of multicomponent perovskites by partial substitution of cations in positions A and B were synthesized by citric acid complex method, giving rise to substituted compounds with common formula of La1-xSrxFeO3 , LaFe1-yCuyO3, La1-xCaxFeO3. It is found that photocatalytic oxidation activity of doped LaFeO3 is higher than pure LaFeO3 which can be testify from analysis of photoacoustic spectra and positron annihilation spectra. In additions, a series of another multicomponent perovskites by partial substitution of cations in positions A and B were synthesized by citric acid complex method, giving rise to substituted compounds with common formula of La1-xSrxCoO3 , LaCo1-yCuyO3, La1-xSrxCo1-yCuyO3,which were used as photocatalysts in the reaction of destruction of phenol. It van be seen that partial substitution of A and B ions is allowed, thus yielding a plethora compounds while preserving the perovskite structure. The trend of photocatalytic oxidation activity of samples by partial substi...
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