Wafer-scale growth of two-dimensional graphitic carbon nitride films

The extension of graphitic carbon nitride (g-CN) materials into optoelectronic applications beyond photocatalysis has long been anticipated due to their non-metallic composition, moderate electronic band gap, and excellent stability. However, large-scale synthesis of uniform two-dimensional (2D) g-CN films with high crystallinity and tunable thickness remains the bottleneck for their future applications in optoelectronic devices. Here, a vapor-phase transport -assisted condensation method has been developed for the wafer-scale synthesis of uniform 2D g-CN films with tunable thickness. First -principle calculations indicate the direct condensation from melem to heptazine-based carbon nitride enables the formation of high -quality g-CN films. A facile water-assisted transfer strategy is developed for subsequent fabrication on arbitrary substrate. A free-standing flexible photodetector array with strain-insensitive responsibility is demonstrated with the g-CN films as imaging pixels. This study provides a convenient route to wafer-scale growth of high-quality 2D g-CN films and paves the way to the g-CN-based electronic and optoelectronic devices.

Automated summary

The study developed a method for wafer-scale synthesis of uniform 2D g-CN films with tunable thickness using vapor-phase transport-assisted condensation. Calculations showed that direct condensation from melem to heptazine-based carbon nitride enabled the formation of high-quality g-CN films. A water-assisted transfer strategy was developed for subsequent fabrication on arbitrary substrates, paving the way for g-CN-based electronic and optoelectronic devices.