To get solutions with specific transparent region,several general inorganic compounds with stable chemical property were selected and prepared into aqueous solutions separately or solutions as mixtures.By measuring the absorption spectrum,5 kinds of solutions were gotten with transparent region and transmittance as follows: ① 0.3mol·L-1 Cr2(SO4)3(≥650nm,99%),② 0.1 mol·L-1 FeCl3 + 0.5 mol·L-1 CuCl2(440-670nm,56%),③ 0.1mol·L-1 Fe2(SO4)3(≥400nm,96%),④0.6mol·L-1 CoCl2 + 0.4mol·L-1 Cu(NO3)2(400±60nm,38%;550-660nm,24%),⑤0.6mol·L-1 CoCl2 + 0.2mol·L-1 Cr(NO3)3(350±30nm,32%,≥620nm,90%).Experiments of photocatalytic degeneration of methylene blue(MB) were done with TiO2 as catalyst and prepared solutions as filters,results indicated that the degradation rate of MB increased with the decrease of transparent wave length which is fit with the law of photocatalytic reaction.
To study the effect of different incendiary agent loading on photocatalytic activity of TiO2,TiO2 powders were prepared with sol-gel auto-igniting synthesis(SAS) method,while tetra-n-butyl titanate and TiCl4 were used as precursor separately.The structure of TiO2 was characterized with XRD and SEM,and photocatalytic activity examined with degradation of methylene blue(MB).Results indicated that TiO2 powders shows as excellent loose and multi-hole material prepared with SAS.With tetra-n-butyl titanate and TiCl4 as precursor,the optimal ratio of n(Ti):n(citric acid):n(NH4NO3)are 1:1:2 and 1:3:5,the according particle sizes are 0.1μm and 20nm,degradation rate constants of MB increase 60% and 100% compared with normal TiO2 powder prepared without SAS method.
