Ultrasound-assisted synthesis of rose-like carbon nitride nanoflowers: synergistic morphology and electronic modulation for efficient CO2 photoreduction

Ultrasound-assisted synthesis of sulfur-doped rose-like C 3 N 4 , which has a 3D nanoflower structure, high S-doping and narrowed bandgap, yielding a 15× higher CO production rate than bulk g-C 3 N 4 and offering a green route to photocatalysts.