Zhao Fenfen, Rong Yuefei, Wan Junmin, Hu Zhiwen, Peng Zhiqin, Wang Bing
National Engineering Lab of Textile Fiber Materials & Processing Technology, Zhejiang Sci-Tech University, Hangzhou, 310018, People's Republic of China.
Nanotechnology. 2018 Mar 9;29(10):105403. doi: 10.1088/1361-6528/aaa68c.
MoS quantum dots (QDs) that are 5 nm in size were deposited on the surface of ultrathin TiO nanotubes (TNTs) with 5 nm wall thickness by using an improved hydrothermal method to form a MoS QDs@TNT visible-light photocatalyst. The ultrathin TNTs with high percentage of photocatalytic reactive facets were fabricated by the commercially available TiO nanoparticles (P25) through an improved hydrothermal method, and the MoS QDs were acquired by using a surfactant-assisted technique. The novel MoS QDs@TNT photocatalysts showed excellent photocatalytic activity with a decolorization rate of 92% or approximately 3.5 times more than that of pure TNTs for the high initial concentration of methylene blue solution (20 mg l) within 40 min under visible-light irradiation. MoS as the co-catalysts favored the broadening of TNTs into the visible-light absorption scope. The quantum confinement and edge effects of the MoS QDs and the heterojunction formed between the MoS QDs and TNTs efficiently extended the lifetime of photoinduced charges, impeded the recombination of photoexcited electron-hole pairs, and improved the visible-light-driven high-efficiency photocatalysis.
通过改进的水热法，将尺寸为5纳米的硫化钼量子点（QDs）沉积在壁厚为5纳米的超薄二氧化钛纳米管（TNTs）表面，以形成硫化钼量子点@二氧化钛纳米管可见光光催化剂。通过改进的水热法，利用市售的二氧化钛纳米颗粒（P25）制备出具有高比例光催化反应面的超薄二氧化钛纳米管，并采用表面活性剂辅助技术获得硫化钼量子点。新型硫化钼量子点@二氧化钛纳米管光催化剂在可见光照射下，对高初始浓度亚甲基蓝溶液（20毫克/升）在40分钟内表现出优异的光催化活性，脱色率达92%，约为纯二氧化钛纳米管的3.5倍。硫化钼作为助催化剂有利于将二氧化钛纳米管的吸收范围拓宽到可见光区域。硫化钼量子点的量子限域和边缘效应以及硫化钼量子点与二氧化钛纳米管之间形成的异质结有效地延长了光生电荷的寿命，阻碍了光激发电子-空穴对的复合，并提高了可见光驱动的高效光催化性能。
