Synergistic carbon defect modulation in porous carbon nitride nanotubes for efficient photocatalytic hydrogen evolution

Abstract

One-dimensional porous nanotubes with specific atomic defect sites are highly attractive for solar-driven photocatalytic water splitting applications. Herein, we demonstrated that carbon nitride nanotubes with constructed carbon vacancies and porous structure could be rationally fabricated by a facile thermal treatment process, leading to remarkable improvements in photocatalytic performances for H₂ production. More specifically, an outstanding H₂ evolution activity of 33.8 mmol g⁻¹ h⁻¹ has been achieved in the presence of cocatalyst Pt, more than 9-fold improvement compared with the pristine carbon nitride (3.7 mmol g⁻¹ h⁻¹). Detailed experiments reveal that carbon vacancies could effectively promote the separation and transport of photogenerated carriers and facilitate the immobilization of the co-catalyst to provide the charge transfer channel. Meanwhile, the porous nanotube structure further enhances the catalyst's optical absorption capacity and hydrophilicity. These demonstrations provide important knowledge for the precise design and fabrication of highly efficient photocatalysts for water splitting.