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

Abstract

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.

Hollow nanocages of vanadium nitride-based electrode material designed for superior charging/discharging stability supercapacitors

“…This provides a practical way to enhance the high specific capacitance. The active materials used in faradaic pseudo-capacitance are mainly conductive polymers, 22 transition metal oxides, 23 hydroxides, [24][25][26] sulfides, 27 and transition metal nitrides, 28 which have a high specific capacitance compared to carbon-based materials, but are more expensive to produce and more complex to process. Ruthenium oxide [29][30][31] (RuO 2 ) was the first metal oxide to be used as a pseudocapacitance electrode material.…”