Mechanically exfoliated g-C3N4 thin nanosheets by ball milling as high performance photocatalysts

g-C3N4 with a layered structure has been proven as an outstanding metal-free organic photocatalyst because of its appropriate bandgap, abundant building elements, and excellent chemical stability. Here, a simple one-step ball milling method is presented for synthesis of mechanically exfoliated g-C3N4 (MECN) thin nanosheets at large scales for the first time. Characterization results showed that gradual size reduction, accompanied by a continual bandgap absorption shift, occurred with increasing grinding time. The obtained MECN thin nanosheets showed significantly enhanced simulated sun light driven photocatalytic activity toward organic degradation compared to their bulk counterpart, highlighting the crucial role of morphology and surface area on the photocatalytic performance.