摘要
提出一种合成h-MoO_(3)纳米棒和h-/α-MoO_(3)复合材料的简易湿法途径,并采用XRD、TG-DSC、FESEMEDX、TEM、FT-IR、拉曼、PL和UV-visDRS光谱等技术对所得产物进行表征。当所用原料液/固比为2:1和5:1时,能够合成单相h-MoO_(3)纳米棒;增加液/固比至8:1和12:1,所得产物则为均质h-/α-MoO_(3)复合材料。根据实验结果,还对h-MoO_(3)的形成机理及其转换成α-MoO_(3)的反应过程进行研究。h-MoO_(3)的淬火过程可分为3个不同的质量损失阶段,分别由物理吸附水、残留铵根离子以及结合水的移除所致。h-MoO_(3)纳米棒和h-/α-MoO_(3)复合材料在亚甲基蓝染料的降解方面均显现出优异的可见光响应光催化性能。由于低的电子-空穴复合率、低的能带跃迁能以及强的吸附-光催化协同作用,h-/α-MoO_(3)复合材料的光催化降解性能更为优异。
A facile hydrothermal route for the synthesis of h-MoO_(3)nanorods and h-/α-MoO_(3)composites was proposed.XRD,TG-DSC,FESEM-EDX,TEM,FT-IR,Raman,photoluminescence(PL)and UV-vis DRS spectroscopy were used to characterize the as-synthesized products.h-MoO_(3)was formed when the liquid/solid ratio of the raw materials was 2:1 and 5:1.However,homogeneous h-/α-MoO_(3)composites were obtained when the liquid/solid ratio was increased to 8:1 and 12:1.A possible mechanism by which h-MoO_(3)is formed,and its transformation intoα-MoO_(3)were investigated.h-MoO_(3)annealing was found to comprise three mass-loss stages;i.e.,the removal of each of the following:physically adsorbed water,residual ammonium,and coordinated water.Both h-MoO_(3)nanorods and h-/α-MoO_(3)composites demonstrated excellent visible-light-driven photocatalytic performance with regard to methylene blue degradation.The superior degradation efficiency of the h-/α-MoO_(3)composites was ascribed to a lower recombination rate of electron-hole pairs,a reduced band gap energy,and an enhanced synergistic effect.
作者
王璐
李红肖
薛正良
Lu WANG;Hong-xiao LI;Zheng-liang XUE(State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China;Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,China)
基金
the financial supports from the National Natural Science Foundation of China(No.52104310)。
