Graphitic carbon nitride and polymers: a mutual combination for advanced properties

The sheet-like material graphitic carbon-nitride (g-C3N4) is one of the most promising metal-free photocatalysts and utilized for various purposes, e.g. energy conversion, waste water remediation or organic synthesis. g-C3N4 features a suitable band gap in the visible light range and outstanding physicochemical stability. However, g-C3N4 features drawbacks such as structural disorder, low conductivity, poor dispersibility and in turn low processability. Amongst the strategies to improve g-C3N4 properties, combination with polymers is a promising avenue toward advanced materials. The present critical review highlights the development and investigation of g-C3N4/polymer combination, including (1) g-C3N4 as photoinitiator for polymer snythesis, (2) polymer modified g-C3N4 for improved dispersibility, (3) g-C3N4/polymer hybrid materials fabricated via physical or covalent attachment and (4) g-C3N4 based hydrogels. The fabrication methods and application of these areas will be critically reviewed and the advantage of g-C3N4/polymer combination comprehensively presented. Moreover, the broad range of applications is highlighted, e.g. photocatalysis, batteries, biosensors, H-2 evolution and films. Finally, the review will conclude with a summary and perspective on future directions as well as current challenges of this research area in order to stimulate new research regarding the design and construction of g-C3N4/polymer materials.