Aluminum storage behavior of anatase TiO2 nanotube arrays in aqueous solution for aluminum ion batteries

Abstract
The electrochemical aluminum storage of anatase TiO2 nanotube arrays in AlCl3 aqueous solution is investigated. It is firstly demonstrated that aluminum ions can be reversibly inserted/extracted into/from anatase TiO2 nanotube arrays in AlCl3 aqueous solution due to the small radius steric effect of aluminum ions, indicating a potential application in aluminum ion batteries.