Operando XAS studies of nickel-iron phosphosulfide nanotube for direct seawater electrolysis

Nickel iron phosphosulfide (NiFeSP) nanotube has been reported to be a promising electrocatalyst for overall direct seawater electrolysis, active for several reactions including the hydrogen/oxygen evolution reactions (HER/OER) and the urea oxidation reaction (UOR) in seawater. Operando XAS collected as a function of applied potentials will provide characterisation of the working state of the novel NiFeSP as well as two reference nickel-iron phosphide (NiFeP) and nickel-iron sulfide (NiFeS) catalysts. Spectra collected at the Ni and Fe edges will allow for identification of structural transformation and the actual active structure and species under HER, OER and UOR conditions, shedding light on the structure-activity relationship of NiFeSP and the promotion mechanism of P and S incorporation.