MoS_2/Bi_2S_3异质结光催化剂的制备及其光催化性能

以五水硝酸铋为铋源、钼酸钠为钼源、硫脲为硫源,采用简单的一步水热法合成了MoS_2/Bi_2S_3异质结光催化剂,采用XRD,SEM,TEM,BET,UV-Vis DRS技术对其进行了表征。表征结果显示,MoS_2纳米片在Bi_2S_3微棒表面生长,增加了比表面积和活性位点,并形成异质结构,促进了光生载流子的迁移,抑制了电子-空穴对的再复合。实验结果表明:钼酸钠与五水硝酸铋的质量比为1∶2时制备的复合光催化剂性能最好,反应180min时对亚甲基蓝的去除率可达96.4%,明显高于MoS_2和Bi_2S_3,且具有较高的稳定性;该催化剂对罗丹明B、甲基橙和4-硝基苯酚的去除率分别为97.1%、93.1%和90.5%,表明其对污染物具有普适性。

Preparation of MoS2/Bi2S3 heterojunction photocatalyst and its photocatalytic activity

MoS₂/Bi₂S₃ heterojunction photocatalyst was synthesized by simple one-step hydrothermal method using bismuth nitrate pentahydrate as bismuth source,sodium molybdate as molybdenum source and thiourea as sulfur source,and characterized by XRD,SEM,TEM,BET and UV-Vis DRS. The characterization results indicated that MoS₂ nanoplatelets grew on the surface of Bi₂S₃ micro-rods,leading to the increase of specific surface area and active sites of the composites and the forming of heterostructure,which promoted the migration of photogenerated electrons and inhibited the recombination of electron-hole pair. The experimental results showed that：When the mass ratio of sodium molybdate to bismuth nitrate pentahydrate was 1∶2,the composite photocatalyst exhibited the best photocatalytic activity and the removal rate of methylene blue reached 96.4% after 180 min,which was much higher than that of MoS₂ and Bi₂S₃;The composite photocatalyst had good stability;The removal rate of rhodamine B,methyl orange and 4-nitrophenol was 97.1%,93.1% and 90.5%,respectively,indicating that the catalyst had universal applicability to pollutants.