A series of La_1‒xSr_xMnO₃ samples were prepared by sol–gel method and used to degrade rhodamine B (RhB) in water. All samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N₂ adsorption–desorption, temperature-programmed reduction of H₂ (H₂-TPR) and temperature-programmed desorption of O₂ (O₂-TPD). The results show that the degradation of RhB is highly dependent on the initial pH value of solution. Sr doping enhances the degradation ability of LaMnO₃ for RhB in the time range of 0–40 min under a strong acidic environment, but all samples exhibit similar degradation rate from 40 to 60 min. In La_0.7Sr_0.3MnO₃–RhB reaction system, there are two different degradation pathways, including N-de-ethylation, chromophore cleavage, ring-opening and mineralization. La_1‒xSr_xMnO₃ (x ≤ 0.3) has the perovskite structure of La–Mn oxides, while La_0.6Sr_0.4MnO₃ exhibits a Sr_0.4MnLa_0.6O_2.98 perovskite phase. Sr doping leads to distortion of rhombohedral crystal structure and increases the relative content of Mn⁴⁺. The perovskite structure is stable in strong acidic environment during RhB degradation, but the relative content of Mn⁴⁺ and Mn³⁺ on the material surface changes. Sr doped LaMnO₃ achieves specific surface area of 58.8 m²/g and total pore volume of 0.152 cm³/g. Furthermore, Sr²⁺ doping improves redox properties of La–Mn oxides, and the presence of defects makes oxygen diffusion easier compared with the undoped samples.

采用溶胶-凝胶法制备了一系列La _{1- x} Sr _x MnO ₃样品，用于降解水中的罗丹明B (RhB)。所有样品均通过 X 射线衍射 (XRD)、X 射线光电子能谱 (XPS)、N ₂ 吸附-解吸、H ₂程序升温还原 (H ₂ -TPR) 和 O ₂程序升温脱附进行表征 （ O ₂ -TPD)。结果表明，RhB 的降解高度依赖于溶液的初始 pH 值。Sr掺杂增强了LaMnO ₃的降解能力在强酸性环境下，在 0-40 分钟的时间范围内对 RhB 进行了降解，但所有样品在 40 至 60 分钟内表现出相似的降解速率。在La _0.7 Sr _0.3 MnO ₃ -RhB反应体系中，有两种不同的降解途径，包括N-脱乙基化、发色团裂解、开环和矿化。La _{1‒ x} Sr _x MnO ₃ ( x  ≤ 0.3) 具有La-Mn 氧化物的钙钛矿结构，而La _0.6 Sr _0.4 MnO ₃具有Sr _0.4 MnLa _0.6 O _2.98钙钛矿相。Sr掺杂导致菱面体晶体结构畸变并增加Mn ⁴⁺的相对含量。RhB降解过程中钙钛矿结构在强酸性环境中稳定，但材料表面Mn ⁴⁺和Mn ³⁺的相对含量发生变化。的Sr掺杂的LaMnO _3个的58.8米达到比表面积² / g和0.152厘米总孔体积³ / g以下。此外，Sr ²⁺掺杂改善了 La-Mn 氧化物的氧化还原性能，与未掺杂的样品相比，缺陷的存在使氧扩散更容​​易。