球状MoS2/WO3复合半导体制备及其对RhB的光催化性能

采用水热法成功制备了MoS₂/WO₃复合半导体光催化剂，分别通过SEM、TEM、EDS、XRD、Raman和DRS对催化剂的形貌，组成及结构进行表征，并用BET模型计算比表面积。对比发现球状MoS₂/WO₃对罗丹明B（RhB）的光降解效率明显高于纯WO₃、片状MoS₂/WO₃复合半导体。针对球状MoS₂/WO₃复合半导体，分别研究了MoS₂不同负载量（0.5%，1%，2%，5%，10%）对RhB光催化降解性能的影响，结果表明MoS₂含量为2%时催化效果最佳。同时，研究了溶液的pH值（pH=1，3，6，7，11）对光催化降解反应活性的影响，结果显示pH=6时降解率最高。当催化剂量增加到1 g·L^-1时，30min后RhB降解率达到96.6%。球状MoS₂/WO₃的瞬态光电流为0.050 6 mA·cm^-2，比纯WO₃提高了2.4倍。经过5次循环实验，球状MoS₂/WO₃复合半导体催化剂仍能保持90%的高降解率。

Spherical MoS2/WO3 Composite Semiconductor:Preparation and Photocatalytic Performance for RhB

MoS₂/WO₃ composite photocatalyst was synthesized by a hydrothermal method. The morphology and structure of samples were respectively characterized by SEM, TEM, XRD, Raman, BET and DRS. Compared with pure WO₃ and flaky MoS₂/WO₃, the results show that spherical MoS₂/WO₃ photocatalysts possess higher photocatalytic efficiency for RhB. For the spherical MoS₂/WO₃ composite semiconductor, the effect of MoS₂ loading content (0.5%, 1%, 2%, 5%, 10%) on the photocatalytic degradation of RhB was investigated. The results show that the catalytic effect is the best when the content of MoS₂ is 2%. At the same time, the effect of pH (pH=1, 3, 7, 11) on the photocatalytic activity was studied. The results show that the degradation rate is the highest at pH=6. When the amount of catalyst is 1 g·L^-1, the degradation rate of RhB reaches 96.6% after 30min. The transient photocurrent of spherical MoS₂/WO₃ is 0.050 6 mA·cm^-2, which is increased by a factor of 2.4 compared with that of WO₃. After five cycles of stability test, the spherical MoS₂/WO₃ composite semiconductor catalyst can maintain a high degradation rate of 90%.