High‐Performance Li–O(2) Batteries with Controlled Li(2)O(2) Growth in Graphene/Au‐Nanoparticles/Au‐Nanosheets Sandwich

The working of nonaqueous Li–O(2) batteries relies on the reversible formation/decomposition of Li(2)O(2) which is electrically insulating and reactive with carbon and electrolyte. Realizing controlled growth of Li(2)O(2) is a prerequisite for high performance of Li–O(2) batteries. In this work, a sandwich‐structured catalytic cathode is designed: graphene/Au‐nanoparticles/Au‐nanosheets (G/Au‐NP/Au‐NS) that enables controlled growth of Li(2)O(2) spatially and structurally. It is found that thin‐layer Li(2)O(2) (below 10 nm) can grow conformally on the surface of Au NPs confined in between graphene and Au NSs. This unique crystalline behavior of Li(2)O(2) effectively relieves or defers the electrode deactivation with Li(2)O(2) accumulation and largely reduces the contact of Li(2)O(2) with graphene and electrolyte. As a result, Li–O(2) batteries with the G/Au‐NP/Au‐NS cathode exhibit superior electrochemical performance. A stable cycling of battery can last 300 times at 400 mA g(−1) when the capacity is limited at 500 mAh g(−1). This work provides a practical design of catalytic cathodes capable of controlling Li(2)O(2) growth.