Multi redox and oxygen vacancies govern the highly active manganese doped SrTiO3 cathode in rechargeable alkaline zinc battery

Rechargeable alkaline zinc batteries (RAZBs) have been facing big challenges of low energy density even they are inexpensive and safe. SrTiO3 has aroused strong interests as cathode of RAZBs based on their promising properties of strong redox properties and better thermal stability. However, the low electric conductivity and inadequate access sites of SrTiO3 limit their applications. Herein, Mn is successfully doped into SrTiO3 using facile one-pot hydrothermal method, which functions as an advanced cathode for RAZBs. In comparison with SrTiO3, partial substitution of Mn for Ti site in SrTiO3 lattice can endow SrTiO3 with enhanced electric conductivity, improved specific surface area as well as active sites of the SrTiO3. This is due to discovery of multi redox reaction of Mn and lattice vacancies. As a result, the Zn//Mn-STO battery demonstrate an excellent capacity of 744 mA h cm-3, good stability, and high energy density of 90 mWh cm-3. These outperforming of Mn-STO as cathode holding a great potential to prepare high-performance battery for future portable electronics.