Binder- and conductive additive-free Ga2O3 nanowires as a self-healing anode for lithium storage

Abstract

High-capacity anode materials have stimulated much attention to developing high-performance lithium-ion batteries. However, high-capacity anode materials commonly suffer from the pulverization matter that greatly hinders their practical applications, especially in terms of the high proportion of active materials. In this work, a Ga2O3 nanowire electrode is synthesized by thermal evaporation and immediately used as an anode without the aid of binders and conductive additives. The 3D interconnected architecture of the Ga2O3 nanowire electrode shortens lithium diffusion lengths and expedites reaction kinetics. The Ga2O3 nanowires exhibit high elasticity and a self-healing ability which is inherited from metallic Ga formed during the electrochemical transition process, thus circumventing the formidable pulverization issue to a certain extent. Benefiting from the unique structural, mechanical, and chemical attributes, the as-grown Ga2O3 nanowire electrode gives a high initial lithiation capacity of 1462 mAh g−1 under a current density of 0.1 ​A ​g−1. It delivers good cyclic stability with a reversible capacity of 445 mAh g−1 after 200 cycles at 0.5 ​A ​g−1. Furthermore, the investigation of lithium storage behaviors indicates the high rate capability of Ga2O3 nanowires. This paper contributes to understanding binder- and conductive additive-free electrodes consisting of high-capacity active materials from various viewpoints.