Enhancement of photocatalytic NO removal activity of g-C3N4 by modification with illite particles

Abstract

Low-concentration nitrogen oxide (NO_x) is a major atmospheric pollutant that can ideally be removed by photocatalysis. At present, photocatalytic techniques for NO removal still suffer from certain problems, such as low efficiency and secondary pollution. In this study, the surface of g-C₃N₄ was modified with illite particles, which not only enhanced the photocatalytic NO removal activity of g-C₃N₄, but also reduced the generation of secondary pollutants (NO₂). This is mainly attributed to the formation of heterojunctions between illite and g-C₃N₄, which promoted charge transfer. Moreover, interface defects and an electric field were formed when the surface of g-C₃N₄ was modified with illite. These interface defects and the electric field could further accelerate interfacial charge transfer. Additionally, modification with illite caused the surface of g-C₃N₄ to peel and roll up. These curls increased O₂ adsorption on the composite to produce more reactive oxygen species. This study provides new insight into the effective utilization of natural minerals in pollution control.