Accelerating photocatalytic hydrogen production by anchoring Pt single atoms on few-layer g-C3N4 nanosheets with Pt-N coordination

Graphitic carbon nitride (g-C3N4) has gained considerable attention as a promising photocatalyst for hydrogen production through water splitting. However, its catalytic efficiency remains severely limited due to the rapid recombination of charge carriers and poor charge-transfer properties. Here, g-C3N4 is subjected to modification through the introduction of well-isolated Pt single atoms using a low-temperature incipient wetness impregnation method. The Pt single atoms exhibit a maximum weight ratio of 1.26%, resulting in a giant enhancement of the photocatalytic H2 evolution rate (336.8 mu mol h-1), approximately two orders of magnitude higher than that of pristine g-C3N4 (1.8 mu mol h(-1)) during a 22-h-long test with an apparent quantum yield (AQY) of 13.5% at 405 nm. The improved performance and excellent stability in photocatalytic H2 evolution can be attributed to the formation of Pt-N bonds between Pt single atoms and g-C3N4, which creates a new energy level of the N 2p-Pt 5d hybrid orbital for remarkably inhibiting the recombination of photogenerated electron-hole pairs and reducing interfacial charge-transfer resistance.