Tb掺杂BiOCl光催化剂的制备及其光催化性能研究

Preparation,property and mechanism of Tb/BiOCl photocatalyst

以五水合硝酸铋、氯化钾、六水合硝酸铽、乙二醇为原料,采用溶剂热法成功制备Tb掺杂氯氧化铋(BiOCl)光催化剂。利用X射线粉末衍射仪、扫描电子显微镜、紫外-可见-近红外光谱仪对样品进行了表征,同时研究了Tb掺杂量对Tb/BiOCl光催化性能的影响,探讨了其可能的光催化机理。结果表明:掺杂Tb可以使BiOCl禁带宽度收窄,同时将光响应区域部分扩展为可见光区;掺杂Tb可以有效地捕捉被激发的电子,从而使降电子和空穴复合的几率减小,Tb掺杂量为1%(摩尔分数)的Tb/BiOCl光催化剂表现出最佳的光催化性能,可见光照射120min后对甲基橙降解率达到了75%,光催化循环实验进行5次后,光催化剂的稳定性仍较高。

Terbium(Tb)doped BiOCl photocatalyst was successfully prepared by solvothermal method using bismuth nitrate pentahydrate,potassium chloride,terbium nitrate hexahydrate and ethylene glycol as raw materials.The samples were characterized by XRD,SEM,and DRS.The effect of Tb doping amount on the photocatalytic activity of BiOCl was studied and the possible photocatalytic mechanism was also discussed.The results showed that the doped Tb can effectively narrow the band gap of BiOCl and extended the light response region to visible light region.Doped Tb can effectively capture the excited electrons,thus reducing the probability of photo-generated electrons and holes recombination.Tb/BiOCl photocatalyst with 1%(mole fraction)Tb doping showed the best photocatalytic performance.After 120min visible light irradiation,the degradation rate of methyl orange reached 75%.After five photocatalytic cycles,the stability of photocatalyst was still high.