p-Block element-doped silicon nanowires for nitrogen reduction reaction: a DFT study

Area of Science:

• Materials Science
• Catalysis
• Green Chemistry

Background:

• Photocatalytic nitrogen reduction reaction (NRR) offers a sustainable route to ammonia (NH₃) synthesis.
• High-performance photocatalysts are crucial for efficient NRR using solar energy.
• One-dimensional silicon nanowires (1D SiNWs) are suitable but lack N₂ affinity.

Purpose of the Study:

• To develop efficient photocatalysts for NRR by doping 1D SiNWs with p-block elements.
• To investigate the NRR performance of boron-doped SiNWs.
• To understand the mechanism behind enhanced NRR activity.

Main Methods:

• Computational screening and theoretical calculations of p-block element-doped SiNWs.
• Focus on two-coordinated boron (B_2C) doped SiNWs for NRR.
• Analysis of overpotential, hydrogen evolution reaction (HER) suppression, and electronic properties.

Main Results:

• Two-coordinated boron (B_2C) doped SiNWs exhibit an ultra-low NRR overpotential (η) of 0.34 V.
• This performance surpasses the benchmark Ru(0001) catalyst (η = 0.92 V).
• Boron doping reduces the band gap and enhances N₂ affinity, suppressing HER.

Conclusions:

• Metal-free, p-block element-based catalysts, specifically B_2C-doped SiNWs, are highly effective for photocatalytic NRR.
• This research advances the development of 1D nanomaterials for efficient and green ammonia production.
• The findings pave the way for utilizing sunlight to convert nitrogen into ammonia under ambient conditions.