In Situ Synthesis of Honeycomb Nanorods Ni<sub>3</sub>S<sub>2</sub>@NiCo-Layered-Double Hydroxide/Nickel Foam Electrocatalysts with High Performance Electrocatalytic Hydrogen Production
Wenhui Liu, Sitong Zhang, Abdulraheem S. A. Almalki, Ahmed M. Fallatah, Zeinhom M. El‐Bahy, Juanna Ren, Xiaoyue Zhao, Ilwoo Seok, Zhanhu Guo
Abstract
High Resolution Image Download MS PowerPoint Slide The design and development of composite nanomaterial structures holds significant importance in the synthesis of highly efficient electrocatalysts. Nevertheless, it is still challenging to obtain advanced electrocatalysts with excellent catalytic activity and stability over the long term. In this study, we successfully obtained a unique nanostructured Ni 3 S 2 @NiCo-layered-double hydroxide (LDH)/nickel foam (NF) by vertically and uniformly growing Ni 3 S 2 ultrafine nanosheets onto the NiCo-LDH surface using NiCo LDH as the backbone. The resulting catalyst possesses a distinctive three-dimensional needle-like nanorod structure, and its surface is composed of numerous two-dimensional cross-defects enriched with honeycomb-like ultrathin nanosheets. This nanostructure design promotes efficient electron transfer, offers abundant active sites, and facilitates the release of gases during the catalytic reactions. Furthermore, the electrocatalyst’s stability and reactivity are greatly enhanced by the synergistic interaction of NiCo LDH with Ni 3 S 2 . Comparative analyses revealed that the Ni 3 S 2 @NiCo LDH/NF catalysts, with their unique three-dimensional needle-like nanorod structure, exhibit superior catalytic performance for the hydrogen evolution reaction (HER) with an electric density of 10 mA·cm –2 and a low overpotential of 151 mV. Remarkably, the catalytic performance of Ni 3 S 2 @NiCo LDH/NF electrocatalysts surpasses that of most nonprecious metal catalysts and even some noble metal catalysts, as reported. In conclusion, the strategy proposed in this study for the construction of cost-effective, extremely active, and stable electrocatalysts holds great potential for future advancements in hydrogen energy conversion applications.