Spontaneous synthesis of Ag nanoparticles on ultrathin Co(OH)2 nanosheets@nitrogen-doped carbon nanoflake arrays for high-efficient water oxidation

The slow four-electron transfer of the oxygen evolution reaction (OER) greatly limits the water splitting efficiency, so the development of high-efficiency and stable OER electrocatalysts is of great significance for large-scale alkaline water splitting. Herein, we reported an efficient self-supported OER electrocatalyst of Ag NPs decorated ultrathin Co(OH)2 nanosheets supported on nitrogen-doped carbon (NC) nanoflake arrays on carbon cloth (Ag/Co(OH)2@NC/CC). Our designed 3D unique electrode structure with heterointerfaces and hierarchical nanosheets endow Ag/Co(OH)2@NC/CC with outstanding OER electrocatalytic activity (300 and 350 mV at 50 and 100 mA/cm2, 79.8 mV/dec of Tafel slope) and good long-term durability in 1 M KOH. Furthermore, the related results of electrochemical tests show that the improved conductivity, increased electrochemical active sites and enhanced intrinsic active sites explain the superior OER performance. Our study will offer some new ideas in constructing new highly-active materials for various other energy conversion fields.