中空球花状MoS2的制备及光催化性能

Preparation and photocatalytic performance of hollow spherical flower-like MoS

以MnCO3为模板,通过水热合成和酸洗两步,可控制备了中空球花状MoS2,采用SEM、BET、XRD和UV-Vis DRS等技术对其形貌、结构和吸光性能进行了表征。以亚甲基蓝为目标降解物,考察了中空球花状MoS2的可见光催化活性及重复使用性。结果表明,在可见光照射下,中空球花状MoS2表现出优异的光催化降解亚甲基蓝的活性,50 mg中空球花状MoS2降解500 mL浓度为5 mg/L的亚甲基蓝溶液,在可见光照射120 min后,亚甲基蓝的降解率为90%,经过5次循环测试,对亚甲基蓝的降解效率没有明显衰减。中空球花状MoS2因其特殊的形貌结构,表现出较窄的禁带宽度(1.5 eV),增强了对可见光的吸收能力,拓宽了对可见光的吸收范围;其特殊的中空球花状结构可有效增大与污染物的接触面积,有较多的边缘活性位点,有序的界面有利于光生电子和空穴的传输与分离,使该材料综合表现出良好的光催化性能且具有良好的稳定性和重复使用性,在光催化降解方面预期有较好的应用前景。

MnCO3 was used as a template to prepare the hollow spherical flower-like MoS2 controllably through two steps of hydrothermal synthesis and pickling.The morphology,structure,and light absorption performance of the as-prepared MoS2 were characterized by SEM,BET,XRD,and UV-Vis DRS.The visible light catalytic activity and recyclability of hollow spherical flower-like MoS2 were investigated with methylene blue as the target degradant.The results show that under visible light irradiation,the hollow spherical flower-like MoS2 exhibits excellent photocatalytic activity toward methylene blue degradation.When 50 mg hollow spherical flower-like MoS2 was used to degrade 500 mL of methylene blue solution with a concentration of 5 mg/L,after 120 min of visible light irradiation,the degradation rate of methylene blue was 90%.After 5 cycles of testing,the degradation rate of methylene blue was not significantly attenuated.Due to its special morphological structure,the hollow spherical flower-like MoS2 presents a narrow forbidden bandwidth(1.5 eV),which can enhance the absorption of visible light,broaden the absorption range of visible light.Moreover,the special hollow spherical flower-like structure can effectively increase the contact area with pollutants and expose more edge active sites.The ordered interface facilitates the transmission and separation of photogenerated electrons and holes so that the material exhibits good photocatalytic performance,excellent stability,and recyclability.The as-prepared hollow spherical flower-like MoS2 is expected to have good application prospects in the photocatalytic degradation of contaminants.