In situ growth of three-dimensional walnut-like nanostructures of W-Ni2P@NiFe LDH/NF as efficient bifunctional electrocatalysts for water decomposition

The design of novel composite nanomaterial structures is important for the construction of advanced electrocatalysts. Nevertheless, obtaining novel electrocatalysts with excellent catalytic activity and stability is still challenging. Herein, new catalysts with a unique nanostructure of W-Ni2P@NiFe LDH/NF composed of W-doped Ni2P ultrafine nanosheets were successfully grown in situ using NiFe LDH nanostructures as the backbone support. The newly produced catalysts showed distinctive three-dimensional spherical nanostructure, beneficial to enhancing electron transport, providing abundant active sites, and promoting gas release. To increase the catalytic effectiveness, a synergy interaction was produced among W-Ni2P with NiFe LDH to yield significantly improved stability and reactivity electrocatalysts. Compared to NiFe LDH/NF and W-Ni2P/NF, the as-obtained spherically-structured W-Ni2P@NiFe LDH/NF catalysts demonstrated high catalytic efficiencies toward OER (222 mV @ 40 mA⋅cm−2), HER (195 mV @ 10 mA⋅cm−2), and total electrolysis (1.7 V @ 10 mA⋅cm−2). Besides, the catalytic activities of W-Ni2P@NiFe LDH/NF electrocatalysts compared well to most published non-precious metal catalysts and even valuable precious metal catalysts. In sum, the proposed approach to construct inexpensive, high-activity, and stable bifunctional electrocatalysts looks promising for advanced future hydrogen energy conversion applications.