采用柠檬酸络合法制备铋层钙钛矿K0.5La0.5Bi2Ta2O9(KLBT),通过酸化处理得到质子化层状钙钛矿H1.90.3La0.5Bi0.1Ta2O7(HKLBT)光催化剂,并通过热重-差热(TG-DSC)、X射线衍射(XRD)、紫外-可见漫反射(DRS)、x射线光电子能谱(XPS)等技术对其进行了表征和分析.考察了前驱体KLBT的不同焙烧温度对HKLBT制氧活性的影响.结果表明,柠檬酸络合法能在较低温度下合成高结晶度纯相HKLBT,前驱体经900℃焙烧制备的HKLBT催化剂活性最高,在纯水中的产氢速率达236.6μmol·h-1:长时间活性测试表明HKLBT具有完全分解水并同时产氢产氧能力,且具有较好的稳定性.
The protonated layered perovskite oxide H1.9K0.3La05Bi0.1Ta2O7 (HKLBT) was prepared from K0.5La0.5Bi2Ta2O9 (KLBT) by H ion-exchange, and subsequently characterized by thermogravimetric analysis (TG-DSC), X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS). The effects of the calcining temperature on the material's photocatalytic activity were also investigated. Results showed that HKLBT with high crystalline quality could be synthesized at low temperatures and that HKLBT prepared from KLBT calcined at 900 ℃ exhibited the greatest photocatalytic activity, with an average water splitting hydrogen evolution rate of 236.6 μmol. h-1 in pure water. The time course of water splitting indicated HKLBT has ability to split water into hydrogen and oxygen with long-term stability.