Layer Stacking-like Iodine and Phosphorus Co-doped C3N4 for Enhanced Visible-light Photocatalytic Hydrogen Evolution

Hetero-element doping is one of the most effective methods for band gap regulation of semiconductor photocatalysts. Here, a novel layer stacking of iodine and phosphorus co-doped carbon nitride (I/P-CN) was prepared from a novel supramolecular precursor. The obtained I/P-CN exhibits significantly enhanced visible-light photocatalytic hydrogen production (93.9 mu mol h(-1)) compared with bulk carbon nitride. Moreover, it reveals a consistent cycle stability for photocatalytic application. The marked improvement in photocatalytic activity is the result of iodine and phosphorus co-doping bringing about a decrease in the band gap and an increase of absorption intensity and width. The unique layer in the stacking structure facilitates an increase in specific surface area and active reaction sites. Our research opens up a new strategy to synthesize multiple elements co-doped carbon nitride as a promising metal-free photocatalyst for hydrogen evolution under visible light.