Surface-growing organophosphorus layer on layered double hydroxides enables boosted and durable electrochemical freshwater/seawater oxidation

Developing high-efficiency and cost-effective electrocatalysts for oxygen evolution reaction (OER) is crucial for hydrogen production from electrolysis. Herein, a facile and universal strategy for fabricating organophosphorus (OP) layer encapsulated layered double hydroxide (LDH) is proposed for robust freshwater/seawater oxidation. This approach is based on a self-growing strategy using phytic acid (PA) to realize superb OER activity due to the electron transfer from metal ions in LDH to the phosphate groups in the OP layer. The phosphate group enriched OP layer can also efficiently avoid chloride corrosion via “physical blocking” and “electrostatic repelling”, enabling the OP-NiCo-LDH catalyst to show durable seawater oxidation catalysis performance. It requires an overpotential of 330 mV to deliver a 500 mA cm^-2 seawater oxidation with excellent durability for 500 h. Moreover, only 1.59 V is required to achieve a 500 mA cm^-2 overall seawater splitting for OP-NiCo-LDH||NiMoN cell. The refore, this work provides a strategy to design robust OER catalysts for industrial water/seawater electrolysis.