“…[22][23][24] Among two-dimensional photocatalysts, g-CN possesses exceptional features such as good thermal stability, recyclability and high catalytic activity. 25,26 This visible light-sensitive metal-free semiconductor can be easily synthesized via thermal condensation of nitrogen-rich and abundant organic monomers at 550 °C. 27 g-CN stands for a family of materials where many parameters such as porosity, light absorption, surface charge, dispersibility and elemental ratio can be adjusted.…”