State Key Laboratory of Urban Water Resource and Environment, School of Environment , Harbin Institute of Technology , Harbin 150090 , China.
ACS Appl Mater Interfaces. 2019 Oct 2;11(39):35720-35728. doi: 10.1021/acsami.9b11322. Epub 2019 Sep 18.
An ordered mesoporous perovskite, LaCoMnO (MLCMO), was synthesized for the first time using a facile method of evaporation-induced self-assembly. The N-sorption, scanning electron microscopy, and transmission electron microscopy measurements indicated that the optimized MLCMO possessed a high specific surface area (58.7 m/g) and was uniformly mesoporous (11.6 nm). The MLCMO exhibited superior catalytic performance in peroxymonosulfate (PMS) activation for atrazine (ATZ) degradation. From a comparison view, the catalytic activity of the mesoporous MLCMO outperformed that of the bulk LaCoMnO (LCMO) and other common PMS activators, including α-MnO, CoO, and CoFeO. The mechanisms of PMS activation by the MLCMO were investigated by X-ray photoelectron spectroscopy, electron spin resonance, and quenching tests. SO, OH, O, and O were identified as main reactive oxygen species generated from PMS activation. The Co and Mn in MLCMO were the active sites responsible for active radical generation. The lattice oxygen reversible redox sites (O/O), which were involved in the electron transfer of the Mn/Mn cycle, were demonstrated as redox partners to the cation active sites. In addition, the SO/OH radical conversion was promoted at pH 11, which accelerated the consumption of PMS and seriously inhibited the degradation of ATZ.
首次采用蒸发诱导自组装的简便方法合成了有序介孔钙钛矿 LaCoMnO（MLCMO）。N 吸附、扫描电子显微镜和透射电子显微镜测量表明，优化后的 MLCMO 具有高比表面积（58.7 m/g）和均匀的介孔（11.6nm）。MLCMO 在过一硫酸盐（PMS）活化方面表现出优异的催化性能，可用于莠去津（ATZ）降解。从比较的角度来看，介孔 MLCMO 的催化活性优于体相 LaCoMnO（LCMO）和其他常见的 PMS 活化剂，包括α-MnO、CoO 和 CoFeO。通过 X 射线光电子能谱、电子顺磁共振和猝灭试验研究了 MLCMO 活化 PMS 的机制。确定 SO、OH、O 和 O 为 PMS 活化生成的主要活性氧物种。MLCMO 中的 Co 和 Mn 是生成活性自由基的活性位点。晶格氧可逆氧化还原位（O/O）参与 Mn/Mn 循环的电子转移，被证明是阳离子活性位的氧化还原对。此外，在 pH 11 下促进了 SO/OH 自由基的转化，这加速了 PMS 的消耗，并严重抑制了 ATZ 的降解。
