A位钡掺杂钙钛矿型LaCoO3光催化剂制备及其光催化降解苯酚性能

Synthesis of A-position Ba-doped Perovskite LaCoO3 and Performance of Photocatalytic Phenol Degradation

中文关键词:  钙钛矿催化剂  La_1-xBa_xCoO₃  光催化  苯酚降解  机理

英文关键词:perovskite catalyst  La_1-xBa_xCoO₃  photocatalysis  phenol degradation  mechanism

中文摘要:

      钙钛矿氧化物材料作为光催化降解水中有机污染物催化剂的应用是一个前景广阔且快速发展的领域. 本文采用柠檬酸配合-水热合成相结合的方法合成出一系列不同Ba掺杂比的La_1-xBa_xCoO₃(x=0.2, 0.3, 0.4, 0.5, 0.6)钙钛矿型光催化剂, 并考察其在可见光下光催化降解苯酚的催化性能. 实验结果表明La_0.5Ba_0.5CoO₃表现出最高的光催化性能.此外, 还讨论了La_0.5Ba_0.5CoO₃的光催化机理. 通过X射线衍射(XRD)、扫描电子显微镜(SEM)、傅里叶变换红外光谱(FT-IR)、X射线电子能谱(XPS)、磁性测量系统(MPMS)等多种表征技术对合成的催化剂进行全面表征, 结果表明, La_1-xBa_xCoO₃的衍射峰强度随着Ba掺杂比的增加而增强, 其中La_0.4Ba_0.6CoO₃的衍射峰最强.催化剂颗粒大小范围为10~50 nm, 且随着Ba含量的增加, 比表面积逐渐降低.此外, La_0.5Ba_0.5CoO₃和La_0.4Ba_0.6CoO₃的顺磁性特征非常相似. 实验结果表明, Ba的掺杂可以显著增强La_1-xBa_xCoO₃钙钛矿的催化性能, 促进电子循环和羟基自由基(?OH)的生成, 从而有效降解苯酚.

英文摘要:

      The utilization of perovskite oxide materials as catalysts for the photodegradation of organic pollutants in water is a promising and rapidly advancing field. In this study, a series of La_1-xBa_xCoO₃ (x=0.2, 0.3, 0.4, 0.5, 0.6) catalysts with varying Ba doping ratios were synthesized using the citric acid complexation-hydrothermal synthesis combined method for the degradation of phenol under visible light irradiation. Among the synthesized catalysts, La_0.5Ba_0.5CoO₃ exhibited the highest photocatalytic activity. In addition, the photocatalytic mechanism for La_0.5Ba_0.5CoO₃ perovskite degradation of phenol was also discussed. The synthesized catalysts were characterized using XRD, SEM, FT-IR, XPS, MPMS and other characterization techniques. The results revealed that the diffraction peak intensity of La_1-xBa_xCoO₃ increased with higher Ba doping ratios, and the La_0.4Ba_0.6CoO₃ exhibited the strongest diffraction peaks. The catalyst particle sizes ranged from 10 to 50 nm, and the specific surface area decreased with increasing Ba content. Additionally, the paramagnetic properties of La_0.5Ba_0.5CoO₃ were similar to that of La_0.4Ba_0.6CoO₃. The experimental results suggested that the incorporation of Ba could significantly improve the catalytic performance of La_1-xBa_xCoO₃ perovskites, promote electron transfer and favor to the generation of hydroxyl radicals (?OH), leading to the efficiently degradation of phenol.