Chlorine doping endows Bi2Te3 with superior charge storage properties as a cathode material for high-performance aqueous zinc-proton hybrid ion batteries

Abstract

To enhance the performance of aqueous batteries, researchers have introduced bismuth chalcogenides as cathode materials in zinc-based batteries. However, their ability to store charge is hindered by low electronic conductivity and poor ion adsorption capability. In this study, we fabricated Cl-doped Bi2Te3 (CBT) sheets through the hydrothermal tellurization of BiOCl plates. Density functional theory (DFT) calculations showed that CBT exhibits conductor-like electrical properties due to electronic structure manipulation. More importantly, the ion adsorption capability of CBT sheets was improved with the introduction of Cl dopant. Consequently, the CBT cathode demonstrated impressive rate capability, achieving a high capacity of 305 mA h g−1 at 0.2 A g−1, and sustaining a capacity of 124.7 mA h g−1 at 30 A g−1. Furthermore, after over 10,000 cycles at 20 A g−1, the reversible capacity remained at 115.8 mA h g−1, demonstrating exceptional cyclic stability.