Due to their high adsorption capacity and low cost, carbon-based materials have experienced great progress in the removal of tetracyclines. Unfortunately, the nature of the adsorption site is far from clarified. Especially, it is still a great challenge to systematically explore the impact of intrinsic defects of carbon-based adsorbents on the adsorption of tetracyclines. Herein, carbon-based adsorbents with different defects were designed and prepared, and their adsorption properties of tetracyclines were systematically studied. From microscopic characterization of carbon-based adsorbents and batch adsorption experiments, the intrinsic defects of carbon-based adsorbents facilitated the adsorption performance of tetracyclines. The best adsorbent (SSG-C) had a very high adsorption capacity (526.9 mg/g for tetracycline (TTC); 360.9 mg/g for oxytetracycline (OTC)). Additionally, density functional theory simulation results show that the ring defects of sp² species promoted the adsorption performance more than sp³ edge defects, and the adsorption performance increased with increasing ring defect of sp² species. Based on the above analysis, we proposed that intrinsic carbon defects activate the π electrons of sp² carbon and facilitate π-π interaction between carbon-based adsorbents and tetracyclines, particularly the ring defects of sp² species. This study provides a decisive contribution to better understanding of the role of intrinsic defects in carbon-based adsorbents for removal of tetracyclines.

由于其高吸附能力和低成本，碳基材料在去除四环素方面取得了很大进展。不幸的是，吸附位点的性质远未阐明。特别是，系统地探索碳基吸附剂的固有缺陷对四环素吸附的影响仍然是一个巨大的挑战。在此，设计和制备了具有不同缺陷的碳基吸附剂，并系统地研究了它们对四环素类的吸附性能。从碳基吸附剂的微观表征和批量吸附实验来看，碳基吸附剂的固有缺陷促进了四环素类的吸附性能。最好的吸附剂 (SSG-C) 具有非常高的吸附容量（四环素 (TTC) 为 526.9 mg/g；360. 土霉素 (OTC) 为 9 mg/g)。此外，密度泛函理论模拟结果表明，环缺陷sp ²物种比sp ³边缘缺陷对吸附性能的促进作用更大，吸附性能随着sp ²物种环缺陷的增加而增加。基于上述分析，我们提出本征碳缺陷激活了sp ²碳的π电子，促进了碳基吸附剂与四环素之间的π-π相互作用，尤其是sp ²物种的环缺陷。这项研究为更好地理解碳基吸附剂中内在缺陷在去除四环素中的作用提供了决定性的贡献。