Emerging investigators series: advances and challenges of graphitic carbon nitride as a visible-light-responsive photocatalyst for sustainable water purification

Abstract

Graphitic carbon nitride (g-C₃N₄) is an emerging visible-light-responsive photocatalyst that has been explored since 2009. This photocatalyst has highly tailorable structures and properties that enable potential utilization of a large portion of solar energy. This material is also synthesized from earth-abundant precursors, is chemically and thermally stable, and is biocompatible with no reported toxicity to date. The merits and pioneering performance evaluation of g-C₃N₄ indicate that this photocatalyst holds promise for the degradation of persistent and emerging contaminants, including chemicals and pathogens, for sustainable water purification with reduced energy and chemical footprint. In this perspective, we propose and answer five questions that are most relevant to the development and application of g-C₃N₄ for photocatalytic water purification, including both benefits and current barriers, from molecular-scale mechanistic understanding of g-C₃N₄ properties and photocatalytic performance to industrial-scale photoreactor design for g-C₃N₄ implementation in practice.