Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China.
Dali Comprehensive Experimental Station of Environmental Protection Research and Monitoring Institute, Ministry of Agriculture and Rural Affairs (Dali Original Seed Farm), Dali, 671004, China.
Environ Sci Pollut Res Int. 2023 May;30(25):66638-66650. doi: 10.1007/s11356-023-27284-8. Epub 2023 Apr 26.
La-based adsorbents are widely used for controlling phosphate concentration in water bodies. In order to explore the effect of different B-site metals regulating La-based perovskites on phosphate adsorption, three La-based perovskites (LaBO, B = Fe, Al, and Mn) were prepared using the citric acid sol-gel method. Adsorption experiments showed that LaFeO exhibited the highest adsorption capacity for phosphate, which was 2.7 and 5 times higher than those of LaAlO and LaMnO, respectively. The characterization results demonstrated that LaFeO has dispersed particles exhibiting larger pore size and more pores than LaAlO and LaMnO. Spectroscopy analysis and density functional theory calculation results showed that different B-positions cause a change in the type of perovskite crystals. Among them, the differences between lattice oxygen consumption ratio, zeta potential and adsorption energy are the main reasons for the differences in adsorption capacity. In addition, the adsorption of phosphate by La-based perovskites were well fitted with Langmuir isotherm and pursues the pseudo-second-order kinetic models. The maximum adsorption capacities were 33.51, 12.31 and 6.61 mg/g for LaFeO, LaAlO and LaMnO, respectively. The adsorption mechanism was mainly based on inner-sphere complexation and electrostatic attraction. This study provides an explanation for the influence of different B sites on phosphate adsorption by perovskite.
基于镧的吸附剂广泛用于控制水体中的磷酸盐浓度。为了探索不同 B 位金属调节镧基钙钛矿对磷酸盐吸附的影响，采用柠檬酸溶胶-凝胶法制备了三种镧基钙钛矿（LaBO，B=Fe、Al 和 Mn）。吸附实验表明，LaFeO 对磷酸盐的吸附容量最高，分别是 LaAlO 和 LaMnO 的 2.7 和 5 倍。表征结果表明，LaFeO 具有分散的颗粒，表现出比 LaAlO 和 LaMnO 更大的孔径和更多的孔。光谱分析和密度泛函理论计算结果表明，不同的 B 位导致钙钛矿晶体类型发生变化。其中，晶格氧消耗比、zeta 电位和吸附能的差异是吸附容量差异的主要原因。此外，磷酸盐在 La 基钙钛矿上的吸附很好地符合 Langmuir 等温线和拟二级动力学模型。LaFeO、LaAlO 和 LaMnO 的最大吸附容量分别为 33.51、12.31 和 6.61 mg/g。吸附机制主要基于内球络合和静电吸引。本研究为不同 B 位对钙钛矿吸附磷酸盐的影响提供了一种解释。
