Porous and low-defected graphitic carbon nitride nanotubes for efficient hydrogen evolution under visible light irradiation

Abstract

Porous and low-defect graphitic carbon nitride (g-C₃N₄) nanotubes were fabricated through heating precursors synthesized by recrystallization from H₂SO₄/methanol. The textural and chemical structures of the as-prepared samples were well studied. Recrystallization and subsequent heating result in g-C₃N₄ nanotubes with developed porosity and high specific surface area. Unexpectedly, the nanotubes exhibit much ordered tri-s-triazine conjugated network and fewer defects. Compared to bulk g-C₃N₄ prepared by direct heating melamine, the nanotubes demonstrate enhanced photocatalytic activity for hydrogen evolution under visible light irradiation. Besides the improved textural and chemical structures, the optimized optical and electronic properties are contributed to the enhanced photocatalytic performance.