Waste Adsorbent-Derived Interconnected Hierarchical Attapulgite@Carbon/NiCo Layered Double Hydroxide Nanocomposites for Advanced Supercapacitors

The attapulgite@carbon/NiCo layered double hydroxide nanocomposites based on waste adsorbents are manufactured via simple and eco-friendly calcination and hydrothermal methods, by which they would be considerable electrode materials for advanced supercapacitors. To achieve sustainable development, the spent tetracycline-loaded attapulgite can act as a cost-effective available carbon source as well as a matrix material for carbon species and NiCo layered double hydroxide simultaneously. A controlled amount of attapulgite@carbon could be used to regulate the electrochemical properties of nanocomposites. The generated electrodes possess superior electrochemical properties with a specific capacitance of 2013.8 F g –1 at 0.5 A g –1, a retention rate of 87.7% at 5 A g –1, and a cyclic stability of 64.9% for 4000 cycles at 5 A g –1 . Thus, the asymmetric supercapacitor device assembled with attapulgite@carbon/NiCo layered double hydroxide nanocomposites||active carbon shows a maximum capacitance of 231.3 F g –1 at 0.5 A g –1, with a preeminent energy density of 82.2 Wh kg –1 when its power density is 4318 W kg –1 . This approach would contribute to the development of supercapacitors in an efficient and effective manner, as well as provide a feasible strategy for solving tetracycline pollution and recycling waste adsorbents to achieve sustainable development.