Next Materials (Jan 2025)
Effect of group III to VII dopants on the band gap and electronic structure of corrugated graphitic carbon nitride
Abstract
Graphitic carbon nitride (GCN) is a versatile photocatalytic material with applications in water treatment, hydrogen production, CO₂ reduction, and organic synthesis due to its 2D structure and semiconducting properties. Its experimental band gap of ∼2.7 eV makes it active under visible light, facilitating photocatalytic reactions such as pollutant degradation, water splitting, and CO₂ conversion. To enhance its utility, strategies to lower GCN's band gap through doping are being actively explored. Transition metal and non-metal doping have been investigated to improve GCN’s light absorption and electronic properties. Non-metal dopants, such as nitrogen, chalcogens, and halogens, offer high electronegativity and covalent bonding potential, leading to improved visible light activity. Despite these advances, detailed understanding of dopants’ atomic-level effects remains limited, making computational studies like density functional theory (DFT) essential. This study examines the effects of main-group element doping on corrugated heptazine-structured GCN. Group III dopants increase the band gap by introducing electron deficiencies, while Groups IV–VII dopants generally reduce the band gap due to larger atomic sizes and weaker electron binding. Unique behaviors, such as high band gaps from nitrogen and fluorine doping, are attributed to their strong electronegativity and small radii. The findings reveal periodic trends in dopant effects on GCN’s band structure, providing insights into rational dopant selection to optimize its electronic properties. These results highlight the potential of tailored doping strategies to enhance GCN’s performance in photocatalysis, energy conversion, and electronic applications.
