Surface/interface nanoengineering for rechargeable Zn–air batteries
Among the various energy storage systems, the rechargeable Zn–air battery is one of the most promising candidates for the consumer electronic market and portable energy sources. In a Zn–air battery, surface/interface chemistry plays a key role in their performance optimization of power density, stability and rechargeable efficiency. A Zn–air battery requires gas-involved ORR (oxygen reduction reaction) and OER (oxygen evolution reaction) reactions, always leading to complex reactions and sluggish kinetic processes at the three-phase interface, in which rational surface/interface nanoengineering at the micro and meso-level play a decisive role. In this review, we cover the influence of surface/interface properties of electrocatalysts and air electrodes on the performance of rechargeable Zn–air batteries, and the latest surface/interface nanoengineering progress from the micro to meso-level is surveyed. Moreover, the surface/interface characteristics of electrocatalysts and air electrodes at the triple-phase interface, which are closely related to the four key parameters of electrical conductivity, reaction energy barrier, reaction surface area and mass transfer behavior, are also described in detail. Based on the discussion of the latest achievements of surface/interface nanoengineering, some personal perspectives on future advanced development of rechargeable Zn–air batteries are presented as well.