School of Metallurgy, Northeastern University, Shenyang 110819, China.
School of Metallurgy, Northeastern University, Shenyang 110819, China.
J Environ Sci (China). 2023 Dec;134:96-107. doi: 10.1016/j.jes.2022.10.019. Epub 2022 Oct 23.
Amorphous manganese oxides (MnO) were synthesized by facile hydrothermal reactions between potassium permanganate and manganese acetate. Synthesis parameters, including hydrothermal time and temperature and molar ratio of precursors, significantly affected the ozone removal performance and structure property of MnO. Amorphous MnO-1.5, which was prepared at the Mn/Mn molar ratio of 1.5 under hydrothermal conditions of 120°C and 2 hr, showed the highest ozone removal rate of 93% after 480 min at the room temperature, RH (relative humidity) = 80% and WHSV (weight hourly space velocity) = 600 L/(g·hr). The morphology, composition and structure of catalysts were investigated with X-ray diffractometer (XRD), Raman spectra, N physisorption, field emission scanning electron microscope (FESEM), X-ray photoelectron spectroscopy (XPS), H temperature-programmed reduction (H-TPR), O temperature-programmed desorption (O-TPD) and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). It was confirmed that high catalytic activity of amorphous MnO for ozone removal was mainly ascribed to its abundant oxygen vacancies, high oxygen mobility and large specific surface area.
无定形锰氧化物 (MnO) 通过高锰酸钾和醋酸锰之间的简单水热反应合成。合成参数，包括水热时间和温度以及前体的摩尔比，显著影响了 MnO 的臭氧去除性能和结构性质。在 Mn/Mn 摩尔比为 1.5 下，在 120°C 和 2 小时的水热条件下制备的无定形 MnO-1.5，在室温、RH（相对湿度）= 80%和 WHSV（重量每小时空间速度）= 600 L/(g·hr) 下，经过 480 分钟后表现出最高的臭氧去除率为 93%。采用 X 射线衍射仪 (XRD)、拉曼光谱、N 物理吸附、场发射扫描电子显微镜 (FESEM)、X 射线光电子能谱 (XPS)、H 程序升温还原 (H-TPR)、O 程序升温脱附 (O-TPD) 和原位漫反射红外傅里叶变换光谱 (in situ DRIFTS) 研究了催化剂的形态、组成和结构。证实了无定形 MnO 对臭氧去除具有高催化活性，主要归因于其丰富的氧空位、高氧迁移率和大比表面积。
