球状MoS_2/WO_3复合半导体制备及其对RhB的光催化性能

Spherical MoS_2/WO_3 Composite Semiconductor:Preparation and Photocatalytic Performance for RhB

采用水热法成功制备了MoS_2/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MoS_2/WO3对罗丹明B(Rh B)的光降解效率明显高于纯WO3、片状MoS_2/WO3复合半导体。针对球状MoS_2/WO3复合半导体,分别研究了MoS_2不同负载量(0.5%,1%,2%,5%,10%)对Rh B光催化降解性能的影响,结果表明MoS_2含量为2%时催化效果最佳。同时,研究了溶液的p H值(p H=1,3,6,7,11)对光催化降解反应活性的影响,结果显示p H=6时降解率最高。当催化剂量增加到1 g·L-1时,30 min后Rh B降解率达到96.6%。球状MoS_2/WO3的瞬态光电流为0.050 6 m A·cm-2,比纯WO3提高了2.4倍。经过5次循环实验,球状MoS_2/WO3复合半导体催化剂仍能保持90%的高降解率。

MoS2/WO3 composite photocatalyst was synthesized by a hydrothermal method. The morphology and structure of samples were resp6ctively characterized by SEM, TEM, XRD, Raman, BET and DRS. Compared with pure WO3 and flaky MoS2/W-O3, the results show that spherical MoSJWO3 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 30 min. 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%.