Delocalized Electrons via In Situ CNT Growth on Au/g-C3N4 for Boosting Photocatalytic H2 Evolution

Graphitic carbon nitride (g-C3N4) is a prominent polymer photocatalyst, yet it suffers from severe charge carrier recombination in photocatalysis. Herein, carbon nanotubes (CNTs) are in situ grown onto g-C3N4 nanosheets via a chemical vapor deposition (CVD) process, catalyzed by Au nanoparticles (NPs) pre-deposited on g-C3N4 surface via deposition-precipitation. Systematic characterizations, in particular femtosecond transient absorption spectroscopy (fs-TAS) and time-resolved photoluminescence (TR-PL), prove that CNTs can efficiently extract the localized electrons in the tri-s-triazine units of g-C3N4, thereby enhancing charge carrier diffusion and separation. As a result, CNT/Au/g-C3N4 nanocomposites display a H-2 evolution rate of 0.95 mmol g(-1) h(-1), which is about three times higher than that of Au/g-C3N4. This work may pave a path to explore the full potential of CNTs to modify g-C3N4 or other photocatalysts in solar-to-chemical energy conversion.

Automated summary

This study investigates the improvement of the photocatalytic performance of g-C3N4 by growing carbon nanotubes on g-C3N4 nanosheets. The results show that carbon nanotubes can efficiently extract localized electrons in g-C3N4, thereby enhancing charge carrier diffusion and separation. This research provides a pathway to utilize carbon nanotubes to enhance the performance of photocatalytic materials.