Porous network of ultrathin V6O13-polyoxometalates nanosheets grown on carbon cloth as anode materials for high-performance lithium-ion batteries

Abstract

Polyoxometalates (POM) have a wide range of applications in electrochemistry, catalysis, and energy storage due to their variable structure and nature. Here, we designed a novel 3D porous network of ultrathin V6O13-POM nanosheets on carbon cloth (V6O13-POM//CC) for the first time by one-pot hydrothermal method with the help of phosphotungstic acid. Serving as inorganic ligands, the anions of phosphotungstic acid coordinate with V cations, facilitating the assembly of nanoclusters and guiding to control of the morphology of V6O13-POM composites, which increases the specific surface area and multiple active sites for the reaction of lithium ions batteries (LIBs). Furthermore, the synergistic effect of V6O13 and POM improves the stability of the structure and increases the capacity of the electrode in LIBs. V6O13-POM//CC as an anode material exhibited a high reversible capacity of 2.03 mAh cm-2 at a high current density of 2 mA cm-2 after 120 cycles. To illustrate the generality of the synthesis strategy, we also obtained MoO3-POM//CC via a similar method. By using V6O13-POM//CC and MoO3-POM//CC as the anode materials, LIBs exhibited high reversible areal specific capacity and excellent cycling stability which are expected to achieve commercial applications.