Metal-Free Brush-Like 3D Carbon Nitride Delivers Efficient Red-Light-Driven Photocatalysis

• • The brush-like 3D carbon nitride (CNS-650) achieved a 7.4-fold higher RhB degradation rate under 660 nm red-light irradiation compared to bulk g-C3N4, demonstrating superior red-light photocatalytic activity. • • Nitrogen-vacancy-rich surface enhances visible-light harvesting, enabling efficient generation of superoxide (O2•−) and hydroxyl (•OH) radicals, which are the primary reactive species for pollutant degradation. • • The 3D brush-like morphology increases accessible active sites and accelerates electron transfer, effectively suppressing charge carrier recombination and improving photocatalytic efficiency. • • The synthesis route via supramolecular self-assembly and calcination offers a scalable, metal-free approach for producing high-performance photocatalysts, potentially reducing costs and environmental impact in wastewater treatment applications.