BiOBr/ATP的制备及光催化降解四环素性能研究

Preparation of BiOBr/ATP and its photocatalytic degradation performance of tetracycline

通过湿式机械化学合成法一步制备了BiOBr/ATP复合光催化剂,利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、红外光谱(FT-IR)和X射线能谱(XPS)等对所制备催化剂的微观结构和形貌进行表征,通过在可见光照射下光催化降解四环素评价催化剂的活性,并考察了其降解四环素类抗生素的性能和机理.结果表明,凹凸棒土棒晶(ATP)与溴氧铋(BiOBr)纳米片之间形成了插层结构,且在ATP质量分数为5%时,复合材料的光催化效果最佳,四环素降解率达到88.23%.通过自由基抑制实验推测主要作用是(·O^(2−)),并提出了可能的四环素降解机制.根据活性物种捕获实验,·O^(2−)和·OH是主要活性物种,h^(+)和e^(−)是次要活性物种.瞬态光电流测试表明,BiOBr/ATP复合光催化剂的光电流增强是BiOBr的1.24倍.

BiOBr/ATP composite photocatalysts were prepared in one step by wet mechanochemical synthesis,and the microstructure and morphology of the prepared catalysts were characterized by scanning electron microscopy(SEM),X-ray diffractometry(XRD),infrared spectroscopy(FT-IR)and X-ray spectroscopy(XPS).And degradation activity of the catalysts were evaluated by photocatalytic degradation of tetracycline under visible light irradiation,and its performance and mechanism for the degradation of tetracycline antibiotics was investigated.The results showed that an intercalation structure was formed between the bumpy clay rod crystals(ATP)and bismuth oxybromide(BiOBr)nanosheets,and the photocatalytic effect of the composites was optimal at a mass fraction of ATP of 5%,with the tetracycline degradation rate reaching 88.23%.The main role was hypothesized to be(·O^(2−))by free radical inhibition experiments,and a possible mechanism of tetracycline degradation was proposed.According to the active species capture experiments,·O^(2−)and·OH were the major active species,and h^(+)and e^(−)were the minor active species.The transient photocurrent test showed that the photocurrent enhancement of BiOBr/ATP composite photocatalyst was 1.24 times higher than that of BiOBr.