MOF-Templated Synthesis of Three-Dimensional B-Doped NiCoP Hollow Nanorod Arrays for Highly Efficient and Stable Natural Seawater Splitting

Abstract

Seawater electrolysis represents a sustainable route for the mass production of high-purity hydrogen fuel. However, the sluggish kinetics of the cathodic hydrogen evolution reaction (HER) remains an excellent challenge for large-scale applications, especially in industrial-level current densities. Here, we report a general strategy to activate three-dimensional (3D) NiCoP hollow nanorod arrays through boron doping, creating high-valence metal centers that are favorable for the water dissociation step. It has been found that the 3D B-NiCoP hollow nanorod arrays can drive a cathodic current density of 10 mA cm −2 at an overpotential of 90, 90, and 98 mV in alkaline freshwater, alkaline simulated seawater, and alkaline natural seawater electrolytes, respectively. The 3D B-NiCoP hollow nanorod array electrocatalyst manifests excellent long-term stability under a high current density of 113 mA cm −2 for more than 85 h in freshwater and seawater electrolytes. Moreover, the 3D B-NiCoP hollow nanorod array electrocatalyst exhibits outstanding HER activity and stability in natural seawater. The study reveals that the exceptional performance for HER is attributed to the high-valence metal centers catalyst, abundant active sites, and efficient charge transfer of the unique 3D structure. This work provides a powerful strategy for designing cost-efficient electrocatalysts for seawater electrolysis.

Multi-metallic Metal–Organic Framework Nanosheets with 3D Flower-like Nanostructure-Based Natural Seawater Splitting toward Stable Industrial-Scale Current Density

“…Therefore, much effort has been made to explore global, cost-effective, and durable electrocatalysts for high-performance seawater electrolysis and, thus, renewable and sustainable hydrogen energy. The growing number of scientific studies on transition-metal-based compound catalysts have drawn a great deal of attention with abundant and outstanding performance electrocatalysts, such as oxides, sulfides, phosphides, selenides, carbides, nitrides, and so forth. Nevertheless, all these nonprecious catalysts are recognized as hardly achieving thriving activity and stability in scaling up applications, which remains a significant challenge. – Therefore, investigating highly active and stable catalysts for seawater electrolysis is desirable and essential for industrial applications.…”

Crystalline-to-Amorphous Transformation and Charge Redistribution Induced by Anion–Cation Double Substitution on 3D Ni(OH)2 Ultrathin Nanosheet Arrays Enable Urea-Assisted Energy-Saving Hydrogen Production

“…The incorporation of alien elements was found to be an advancing strategy to improve catalytic performance via electronic structure modulation and heterojunction formation. Anions, such as P, N, S, and F, are usually doped into the matrix by replacing or substituting host materials to reconstruct the catalyst to improve electrical conductivity and provide a more active phase of catalysts. − For example, the anion doped of sulfur and selenide in a solid solution of CoFe layered double hydroxide shows a significantly enhanced electrocatalytic performance toward the OER compared with its host . They found that anion doping induced fast electron transfer and low diffusion resistance and exposed more active sites, which contributed to the high catalytic activity.…”