Point-Defect Engineering: Leveraging Imperfections in Graphitic Carbon Nitride (g-C3N4) Photocatalysts toward Artificial Photosynthesis

Graphitic carbon nitride (g-C3N4) is a kind of ideal metal-free photocatalysts for artificial photosynthesis. At present, pristine g-C3N4 suffers from small specific surface area, poor light absorption at longer wavelengths, low charge migration rate, and a high recombination rate of photogenerated electron-hole pairs, which significantly limit its performance. Among a myriad of modification strategies, point-defect engineering, namely tunable vacancies and dopant introduction, is capable of harnessing the superb structural, textural, optical, and electronic properties of g-C3N4 to acquire an ameliorated photocatalytic activity. In view of the burgeoning development in this pacey field, a timely review on the state-of-the-art advancement of point-defect engineering of g-C3N4 is of vital significance to advance the solar energy conversion. Particularly, insights into the intriguing roles of point defects, the synthesis, characterizations, and the systematic control of point defects, as well as the versatile application of defective g-C3N4-based nanomaterials toward photocatalytic water splitting, carbon dioxide reduction and nitrogen fixation will be presented in detail. Lastly, this review will conclude with a balanced perspective on the technical and scientific hindrances and future prospects. Overall, it is envisioned that this review will open a new frontier to uncover novel functionalities of defective g-C3N4-based nanostructures in energy catalysis.

Automated summary

Graphitic carbon nitride (g-C3N4) is an ideal metal-free photocatalyst for artificial photosynthesis, but its original structure suffers from limitations which can be significantly improved through defect engineering for enhanced photocatalytic activity, holding great significance for solar energy conversion advancements.