Calcium-based materials are considered to be promising adsorbents for phosphate removal in the water environment due to their environmental friendliness and low price. However, improving the efficiency and rate of P adsorption of calcium-based materials still needs further exploration. In this study, a high-efficiency and eco-friendly Ca/Fe composite was rationally designed and fabricated by a co-precipitated method. Batch adsorption experiments showed that Ca/Fe composites with a Ca: Fe molar ratio of 3: 1 exhibited a remarkable phosphate sorption capacity of 161.4 mg P/g. Furthermore, the phosphate adsorption capacity of Ca/Fe-3/1 composite was maintained relatively high at pH 3-11 due to the ligand exchange, electrostatic and chemical precipitation. In addition, the experiment performed to determine the effect of coexisting ions shows that only carbonate ions slightly inhibit the phosphate adsorption effect of the Ca/Fe-3/1 composite. The newly prepared Ca/Fe composites have a fast phosphate removal efficiency. The XPS and EPR analysis showed that a large number of oxygen vacancies were formed on Ca/Fe composites due to the introduction of magnetic Fe. This is the first time to introduction oxygen vacancies into Ca/Fe composites by co-precipitation. The existence of oxygen vacancies can promote electron transfer rate and reduce the bonding energy barrier for phosphate adsorption, thereby increasing the phosphate absorption rate of the Ca/Fe composites. The enhanced phosphate removal by Ca/Fe composites with abundant oxygen vacancies provides a new strategy for the preparation of commercial phosphate -controlling materials.

由于钙基材料对环境友好且价格低廉，因此被认为是在水环境中去除磷酸盐的有前途的吸附剂。但是，提高钙基材料对P的吸附效率和吸附速率仍需进一步探索。在这项研究中，通过共沉淀法合理设计和制造了一种高效且环保的Ca / Fe复合材料。分批吸附实验表明，Ca / Fe摩尔比为3：1的Ca / Fe复合材料具有161.4 mg P / g的显着磷酸盐吸附能力。此外，由于配体交换，静电和化学沉淀，Ca / Fe-3 / 1复合材料的磷酸盐吸附能力在pH 3-11保持相对较高。此外，为确定共存离子的影响而进行的实验表明，只有碳酸根离子会稍微抑制Ca / Fe-3 / 1复合材料的磷酸根吸附作用。新制备的Ca / Fe复合材料具有快速的磷酸盐去除效率。XPS和EPR分析表明，由于引入了磁性铁，在Ca / Fe复合材料上形成了大量的氧空位。这是第一次通过共沉淀将氧空位引入Ca / Fe复合材料中。氧空位的存在可以促进电子传输速率并降低磷酸盐吸附的键能垒，从而提高Ca / Fe复合材料的磷酸盐吸收速率。