This study utilized a straightforward co-precipitation method to successfully synthesize Ce-La-X(Mn/Pr)-O composite materials for treating simulated hexavalent chromium (Cr(VI)) wastewater with distinctively porous and fluffy textures, along with tubular morphologies. Notably, Ce-La-Mn-O demonstrated a remarkable specific surface area of 96.2698 m2/g, mesoporous architecture with a pore diameter of 6.9511 nm, and an impressive adsorption capacity of 88.79 mg/g. Under optimized conditions, specifically an initial Cr(VI) concentration of 20 mg/L, a Ce-La-Mn-O dosage of 0.8 g/L, a reaction temperature of 40 °C, an initial pH of 6, and with the application of simulated daylight, the removal rate of Cr(VI) exceeded 98% within 15 min. Even after three cycles, the removal rate was maintained at above 80%. Based on a comprehensive suite of morphological, structural, and performance characterizations, the introduction of Mn/Pr was found to modify the structure of Ce-La-O and enhance the synergistic interactions among the metals within the Ce-La-O framework. In addition, Ce-La-Mn-O exhibited superior visible light absorption properties and dual functionality for catalytic reduction and adsorption. All three materials were found to form -OH polar bond functional groups, converting it to Cr(III) and subsequently forming Cr(OH)3. The Ce-La-X(Mn/Pr)-O composite materials provide a robust theoretical foundation for exploring the dual functional synergistic effects in the efficient removal of Cr(VI) from aqueous systems, indicating their vast potential for practical applications.

中文翻译：

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共沉淀和协同光催化降解 Cr(VI) 合成 Ce-La-Pr/Mn-O 三元氧化物复合材料

本研究利用简单的共沉淀方法成功合成了 Ce-La-X(Mn/Pr)-O 复合材料，用于处理模拟六价铬 (Cr(VI)) 废水，该材料具有独特的多孔和蓬松质地以及管状形态。值得注意的是，Ce-La-Mn-O 表现出惊人的比表面积（96.2698 m2/g）、孔径为 6.9511 nm 的介孔结构以及令人印象深刻的吸附容量（88.79 mg/g）。优化条件下，Cr(VI)初始浓度为20 mg/L，Ce-La-Mn-O用量为0.8 g/L，反应温度为40 ℃，初始pH为6，应用模拟日光，15分钟内Cr(VI)去除率超过98%。即使经过三个循环，去除率仍保持在80%以上。基于全面的形态、结构和性能表征，发现Mn/Pr的引入可以改变Ce-La-O的结构并增强Ce-La-O框架内金属之间的协同相互作用。此外，Ce-La-Mn-O表现出优异的可见光吸收性能以及催化还原和吸附的双重功能。发现所有三种材料均形成 -OH 极性键官能团，将其转化为 Cr(III)，随后形成 Cr(OH)3。 Ce-La-X(Mn/Pr)-O复合材料为探索从水体系中有效去除Cr(VI)的双功能协同效应提供了坚实的理论基础，表明了其巨大的实际应用潜力。