Crassula perforata structured Ni3S2/NiTe electrodes enable efficient and robust seawater electrolysis at industrial-level current density

A crassula perforata structure composed of Ni 3 S 2 nanosheets strung by NiTe nanorods at nickel foam is designed. The transformation of S to sulfate and Ni to (oxy)hydroxides results in high seawater electrolysis due to tailored d-band center and smoothed absorption/desorption of intermediates. • Crassula perforata structure composing of Ni 3 S 2 nanosheets strung by NiTe nanorods . • Both electrolyte immersion/diffusion and electron transfer from NiTe to Ni 3 S 2 are boosted. • Covalency of NiTe is weakened and the electronegativity of Ni 3 S 2 is lowered. • During OER, the S is oxidized to sulfate and Ni species are transformed into (oxy)hydroxides. • Tailored d-band center and smoothed absorption/desorption result in efficient and robust seawater electrolysis. An in-situ prepared crassula perforata structure composing of Ni 3 S 2 nanosheets strung by NiTe nanorods at nickel foam (Ni 3 S 2 /NiTe/NF) is well-designed for seawater electrolysis. The crassula perforata structure provides more exposed Ni 3 S 2 /NiTe interfaces, and the gaps between Ni 3 S 2 nanosheets can accommodate the electrolyte solution, which not only boosts the electrolyte immersion/diffusion but induces strong electron transfer from NiTe to Ni 3 S 2 , to weaken the covalency of NiTe and lower the electronegativity of Ni 3 S 2 . Thus, during oxygen revolution reaction, the S species can be oxidized into sulfate layer and Ni species are transformed into nickel (oxy)hydroxides, with tailored d-band center and smoothed absorption/desorption of oxygen intermediates. Importantly, the in-situ generated sulfates play a crucial role in suppressing chloride corrosion. In addition, the gaps between Ni 3 S 2 sheets provide enough space for the structural change of materials during water splitting, thus improving the catalytic stability. The Ni 3 S 2 /NiTe/NF (+, −) electrolyzer only needs 2.1 V to drive a current density of 1.0 A cm −2 for 100 h in 6 M KOH mixed seawater at 60 °C. In this work, the synthesis of crassula perforata structured Ni 3 S 2 /NiTe/NF electrode provides a novel approach for the development of highly efficient and robust catalysts for industrial seawater electrolysis.