光源的选择对水溶性磺酸卟啉光催化对萘二酚类物质催化性能的影响

制备了水溶性磺酸卟啉(TPPS, TMPPS)及其铁配合物(FeTPPS). 以过氧化氢为氧源、 碘钨灯为光源, 水溶性磺酸卟啉可以高效光催化氧化1,5-萘二酚, 产物为5-羟基-1,4-萘二醌. 测定了卟啉的荧光量子产率及寿命, 分析了催化机理. 选择波长在350~650 nm区间内6个波段和功率在0~20 W区间内4种功率的光源, 探索了不同波段及功率的光源对卟啉光催化活性的影响. 研究结果表明, 不同波段的光源对卟啉光催化1,5-萘二酚的催化活性顺序为λ_380—385>λ_360—370>λ_580—585>λ_620—630>λ_492—577>λ_450—470, 该活性顺序与卟啉的紫外-可见吸收密切相关; 当使用相同波段光源时, 卟啉配体催化氧化1,5-萘二酚的反应速率常数与功率呈良好的线性关系; 卟啉铁配合物随着光源功率的增大, 其催化活性与光解程度有直接关系.

Effect of Light Source on the Photocatalytic Performance of Dihydroxynaphthalene by Water-soluble Sulfonated Porphyrins

Water-soluble sulfonated porphyrins（TPPS， TMPPS and FeTPPS） were synthesized. Taking hydrogen peroxide as the oxidant and iodine-tungsten lamp as the light source， these porphyrins can photo-catalyze the oxidation of 1，5-dihydroxynaphthalene efficiently， the product is 5-hydroxy-1，4-naphthalene-diquinone. The fluorescence quantum yield and lifetime were measured， and the catalytic mechanism was analyzed. The effect of light sources under different wavelength range（350―650 nm） and power range（0―20 W） on the photo-catalytic activities by different porphyrins were investigated. It is shown that light sources with different wave bands have a certain effect on the photocatalytic performance of porphyrin catalysts. The order of the reactant conversion rate is： λ_380―385>λ_360―370>λ_580―585>λ_620―630>λ_492―577>λ_450―470， which has close correlation with the ultraviolet-visible absorption of porphyrins. For free base porphyrins， when the same wavelength band of the light source was used， the reaction rate constants show fine linear relation with the power of the light source. For iron porphyrin FeTPPS， because of its photolysis， its catalytic activities are greatly depending on the catalyst stabilities at different power of the light sources.