Effective Prevention of Charge Trapping in Graphitic Carbon Nitride with Nanosized Red Phosphorus Modification for Superior Photo(electro)catalysis

The high occurrence of trapped unreactive charges due to chemical defects seriously affects the performance of g-C3N4 in photocatalytic applications. This problem can be overcome by introducing ultrasmall red phosphorus (red P) crystals on g-C3N4 sheets. The elemental red P atoms reduce the number of defects in the g-C3N4 structure by forming new chemical bonds for much more effective charge separation. The product shows significantly enhanced photocatalytic activity toward hydrogen production. To the best of our knowledge, the hydrogen evolution rate obtained on this hybrid should be the highest among all P-containing g-C3N4 photocatalysts reported so far. The trapping and detrapping processes in this red P/g-C3N4 system are thoroughly revealed by using time-resolved transient absorption spectroscopy.