Single B-vacancy enriched α₁-borophene sheet: an efficient metal-free electrocatalyst for CO₂ reduction

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Developing efficient metal-free electrocatalysts is crucial for sustainable energy technologies.
• Carbon dioxide (CO2) reduction offers a pathway to convert greenhouse gases into valuable chemicals.
• Borophene, a 2D material, presents unique electronic properties for catalytic applications.

Purpose of the Study:

• To investigate the potential of pristine and defective borophene sheets as electrocatalysts for CO2 reduction.
• To understand the role of structural defects in enhancing catalytic activity.
• To identify the preferred reaction pathways and products for CO2 electroreduction on borophene.

Main Methods:

• First principles calculations were employed to study the electronic structures of borophene sheets.
• Density Functional Theory (DFT) was used to model CO2 adsorption and activation.
• Calculations of reaction pathways, activation energies, and onset potentials were performed.

Main Results:

• Pristine and some defective borophene sheets showed limited CO2 interaction.
• A specific defective borophene (α1-) effectively chemisorbed and activated CO2.
• The α1- defect facilitated the selective conversion of CO2 into C1 (e.g., CH3OH, CH4) and C2 (e.g., CH3CHO, CH3CH2OH) products.
• Low onset potentials were computed for C1 and C2 products, outcompeting the hydrogen evolution reaction.

Conclusions:

• Defective borophene sheets, particularly α1-, are promising metal-free electrocatalysts for CO2 reduction.
• The identified defect significantly enhances CO2 activation and selectivity towards valuable chemical products.
• This study highlights the potential of tailored borophene structures for sustainable electrocatalysis.