MoS2/TriO2复合催化剂的制备及其在紫外光下的光催化制氢活性

摘要

To study the activity of a composite photocatalyst for photocatalytic hydrogen production,we prepared and loaded MoS2 nanosheets with TiO2 nanoparticles using a hydrothermal method,thus forming a MoS2/TiO2 heterojunction composite catalyst.The structural and optical properties of the catalyst were characterized and analyzed by field-emission scanning electron microscopy,high-resolution transmission electron microscopy,X-ray powder diffraction,UV-Vis absorption spectra,Raman spectroscopy,and X-ray photoelectron spectroscopy.The activity of the photocatalyst was evaluated by its photocatalytic hydrogen production rate.The corresponding MoS2 content of the catalyst was found to be 30％,and upon the exposure to 365nm UV light,a high photocatalytic hydrogen production rate of 1004 μmol-1.h-1·g-1 was obtained.The catalytic rate is much greater than that obtained with MoS2 or Tio2 catalysts.The high hydrogen production rate indicated that the use of a MoS2/TiO2 composite catalyst can significantly improve the UV-induced photocatalytic hydrogen production performance.Because of the excellent photocatalytic hydrogen production performance of the MoS2/Tio2 composite,we studied and analyzed the hydrogen production mechanism.%为了研究复合光催化剂在光催化中的制氢效率,采用水热法制备了MoS2纳米片,然后通过水热法在MoS2纳米片上负载了TiO2纳米颗粒,形成了MoS2/TiO2异质结复合催化剂.采用冷场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)、×射线衍射(XRD)、紫外-可见吸收光谱(UV-Vis)、拉曼光谱(Raman),X射线光电子能谱(XPS)对材料的结构和光学性能表征并进行分析.通过光催化制氢测试对光催化剂进行评价,实验结果表明,在波长为365 nm的紫外光照射下,最高光催化制氢速率为1004 μmol·h-1.g-1,对应的催化剂的MoS2含量为30％,其催化速率远大于单一的MoS2和TiO2,表明MoS2/-iO2复合催化剂在紫外光照下能显著提高光催化产氢性能.基于MoS2/TiO2复合光催化剂优越的光催化产氢性能,本文对复合光催化剂的产氢机理做了研究和分析.