不同形貌钛酸钡纳米晶体的光催化性能研究

采用水热法,分别利用聚乙二醇200(PEG200)和乙醇的调控作用,合成了十二面体和立方块两种不同形貌的钛酸钡(BaTiO_3,BTO)纳米晶体,两种晶体分别具有(110)和(100)不同的晶面。利用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)以及UV-Vis漫反射光谱对BTO纳米晶体进行表征分析,结果显示十二面体BTO纳米晶体具有较小的粒径,较大的表面活性;而立方块BTO纳米晶体具有较大的粒径,较小的表面活性。在相同条件下对甲基橙进行光催化降解实验,十二面体BTO纳米晶体显示出优于立方块BTO纳米晶体的催化性能。光催化动力学理论模拟结果进一步证实了上述实验结果。

Photocatalytic Properties of Barium Titanate Nanocrystals with Different Morphologies

Dodecahedral and cubic barium titanate (BaTiO 3, BTO) nanocrystals with two different morphologies were synthesized by hydrothermal method using polyethylene glycol 200 (PEG200) and ethanol respectively. The two kinds of nanocrystals have (110) and (100) different crystal planes. BTO nanocrystals were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-Vis diffuse reflectance spectroscopy. The results show that dodecahedral BTO nanocrystals have smaller particle size and larger surface activity, while cubic BTO nanocrystals have larger particle size and small surface activity. The photocatalytic degradation of methyl orange under the same conditions show that dodecahedral BTO nanocrystals exhibit better catalytic performance than cubic BTO nanocrystals. The theoretical simulation results of photocatalytic dynamics further confirm the above experimental results.