Boosting oxygen evolution reaction activity and durability of phosphate doped Ni(OH)2/FeOOH hierarchical microtubes by morphology engineering and reconstruction strategy

Abstract

Developing electrocatalysts with remarkable activity and durability is significant for efficient oxygen evolution reaction (OER). Herein, we designed phosphate doped Ni(OH)2/FeOOH hierarchical microtubes (denoted as POx-Ni(OH)2/FeOOH HMTs), obtained by phosphate doped NiFe Prussian blue analogue hierarchical microtubes (denoted as P-NF-PBA HMTs) completely reconstructing in OER process. POx-Ni(OH)2/FeOOH HMTs possess an extremely low overpotential of 237 mV at 30 mA cm−2 in alkaline electrolyte with the Tafel slope of 35 mV dec−1, and the catalysts can maintain excellent durability for 100 h at 30 mA cm−2. The remarkable electrochemical catalytic activity comes from the advantages of the hierarchical hollow structure, the modulation of electronic structure caused by phosphate doping, and the synergistic effect of Ni(OH)2 and FeOOH species produced by catalyst complete reconstruction in the OER process. This work may provide an effective strategy to develop highly efficient and durable electrocatalysts towards OER.