Surface Geometry-Electronic Structure Synergy in SbN₄-Rich Multidimensional Nanocarbon Boosts Triiodide Reduction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrocatalyst design is crucial for efficient chemical reactions.
• Optimizing active sites, charge transfer, and intermediate adsorption enhances catalytic activity.
• Carbon-based materials offer tunable properties for electrocatalysis.

Purpose of the Study:

• To fabricate a multidimensional carbon catalyst with atomic antimony coordinated with nitrogen (SbN4).
• To investigate the catalyst's efficacy in triiodide reduction.
• To elucidate the structure-performance relationships in carbon-based electrocatalysts.

Main Methods:

• Controlled chemical unzipping of carbon nanotubes (CNTs) followed by antimony incorporation.
• Fabrication of a carbon heterostructure with CNTs and graphene nanoribbons.
• Electrochemical characterization and theoretical investigations.

Main Results:

• The SbN4-enriched catalyst (Sb-NDHC-800) exhibited over twice the electrochemically active surface area of pristine CNTs.
• Sb-NDHC-800 demonstrated ultralow charge-transfer resistance and a short electron lifetime.
• Theoretical studies confirmed optimized intermediate adsorption due to tuned electronic structure and SbN4 sites.

Conclusions:

• The fabricated SbN4-containing carbon heterostructure is a highly effective electrocatalyst for triiodide reduction.
• Surface structure manipulation and SbN4 coordination are key to enhancing electrocatalyst performance.
• This work provides valuable insights for designing advanced carbon-based electrocatalysts.