Direct Conversion of Metal Organic Frameworks into Porous Rugby Phosphides by Plasma for Oxygen Evolution.

Electrolytic seawater is a green, sustainable, and promising approach for hydrogen production. Benefiting from the cost-effectiveness, crystal structures, and tailorable modification, transition metal phosphides become a highly attractive catalyst for the electrolysis of water. Considering the sufficient exposure and intrinsic catalytic activity of metal sites, here, carbon layer-coated NiFeP nanocrystals with a porous rugby structure are synthesized by Ar-H plasma. Activated PH radical in plasma is the key point to achieve phosphatization at a low temperature. The obtained porous rugby NiFeP catalyst exhibits excellent catalytic activity under alkaline conditions (300 mV in freshwater and 370 mV in seawater, 1000 mA cm), good corrosion resistance, and superior operational stability (>100 h). Theoretical calculations prove that Fe introduction and subsequent phosphorization weaken the adsorption of *O and *OH, thus improving the oxygen evolution reaction performance. Plasma phosphorization offers exciting opportunities for the in situ modification of other types of framework materials.