Introducing defects into metal oxides is considered as an effective method to improve their performance. However, to fully understand the role of oxygen vacancies in the adsorption of organic dyes is still a challenging target. Herein, defective alumina (DF-AlOx) microspheres were synthesized and used as adsorbents for removing organic dyes. In contrast to ordinary Al₂O₃, the DF-AlOx has an amorphous structure. The DF-AlOx possesses abundant coordinatively unsaturated Al-species, oxygen vacancies and oxygen-containing groups. The DF-AlOx exhibited excellent adsorption performance for dyes compared to Al₂O₃. The maximum adsorption capacities for congo red (CR), methylene blue (MB) and methyl orange (MO) estimated from the Langmuir model are 1156.5, 349.5 and 1270.8 mg/g, respectively. Based on the experimental data and density functional theory (DFT) calculations, a vacancy capture mechanism for enhanced adsorption of dyes was proposed. Compared with Al₂O₃, oxygen vacancies can be easily generated on the DF-AlOx surface, which mainly act as the capture centers and facilitate the adsorption of dyes. This work may shed light on designing high-efficiency adsorbents and further investigation of adsorption mechanism for organic dyes removal.

将缺陷引入金属氧化物被认为是改善其性能的有效方法。但是，要充分了解氧空位在有机染料吸附中的作用仍然是一个具有挑战性的目标。在此，合成了有缺陷的氧化铝（DF-AlOx）微球，并用作去除有机染料的吸附剂。与普通的Al ₂ O _3相比，DF-AlOx具有非晶结构。DF-AlOx具有丰富的配位不饱和Al-物种，氧空位和含氧基团。与Al ₂ O ₃相比，DF-AlOx对染料的吸附性能优异。根据Langmuir模型估算，刚果红（CR），亚甲基蓝（MB）和甲基橙（MO）的最大吸附容量分别为1156.5、349.5和1270.8 mg / g。基于实验数据和密度泛函理论（DFT）的计算，提出了一种空位捕获机制，以增强染料的吸附。与Al ₂ O ₃相比，DF-AlOx表面上容易产生氧空位，其主要充当捕获中心并促进染料的吸附。这项工作可以为设计高效吸附剂和进一步研究吸附去除有机染料的机理提供参考。