Controllable Preparation and Sodium Storage Properties of Sb₂Te₃-Te Heterojunction

Antimony-based materials possess high theoretical capacities and suitable potential, which could be promising anode materials for sodium-ion batteries (SIB). However, poor stabilities and sluggish kinetics are drawbacks. Building heterojunction is an ideal method to solve these issues. Its unique structure develops internal electric fields spontaneously to boost the charge transport and relieve stress. Nevertheless, the controllable preparation of face-to-face (2D) heterojunctions is still hard-pressed. Herein, Sb2Te3-Te nanoheterojunctions, which consist of two-dimensional Sb2Te3 nanoblades attached to a one-dimensional Te nanorod, are fabricated through a two-step solvothermal method. Among that, the density of nanoblades is adjustable through the engineering feed ratio. When employed as anodes for SIBs, Sb2Te3-Te nanoheterojunctions display a reversible capacity of 463.2mAhg(-1) at 100mAg(-1). Even a capacity of 305.5mAhg(-1) remains after 1000 cycles under a high current of 1.5Ag(-1). Moreover, the density functional theory (DFT) calculations also identify the high conductivity of heterojunction. This work offers an effective way to design the structures and properties of heterojunctions, further expanding their application range.