Interfacial FeOOH/CoO nanowires array improves electrocatalytic water splitting

Interface engineering has become an effective strategy to improve the electrocatalytic performance because of the strong coupling and synergistic effects between individual components. Herein, both interfacial FeOOH/CoO nanosheets (FeOOH/CoO-NSs) and nanowires array (FeOOH/CoO-NWs) were in situ constructed on nickel foam (NF) through a simple one-step hydrothermal approach. The rational selection of Fe(NO3)(3)center dot 9H(2)O as a Fe source prevents the formation of nanosheet, and enables the generation of nanowire structure due to chemical affination. Benefiting from the synergistic interaction between FeOOH-CoO interface and the unique nanowires array structure, the resultant FeOOH/CoO-NWs/NF exhibits outstanding electrocatalytic activity towards both OER and HER. For the overall water splitting, the bifunctional FeOOH/CoO nanoneedle catalyst requires a cell voltage of only 1.61 V to achieve a current density of 10 mA cm(-2), which is much lower than that required for IrO2 parallel to Pt/C (1.62 V). The present work provides a new horizon to design highly efficient water splitting catalysts through synergistic modulation of interface and micro-nano structures.

Automated summary

Interface engineering is an effective strategy to enhance electrocatalytic performance through synergistic modulation of interface and micro-nano structures. The FeOOH/CoO-NWs/NF catalyst exhibits outstanding activity towards OER and HER, requiring a lower cell voltage for overall water splitting compared to IrO2 parallel to Pt/C.