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.
