Fabrication of electron’s path based on carbonized polymer dots to accelerate photocatalytic hydrogen production kinetic for carbon nitride

Constructing efficient path for electron mobility is significant for increasing carrier separation and transport ability but a great challenge. Herein, a unique shell based on carbonized polymer dots (CPDs) is fabricated to serve as electron’s path for charge transfer from carbon nitrides (CN) to metal-based cocatalysts. This CPDs shell homogenously fixes each CPD on the catalyst surface through metal-N bonding, and possesses strong electron extraction ability by masterly controlling the pyridinic N structure. As a result, the obtained CN/MoP@CPDs-200 achieves an outstanding apparent quantum efficiency (9.4% at 450 nm), which is superior to CN/3 wt% Pt. Importantly, in-depth transient photo-induced voltage studies confirm the excellent charge extraction ability of CPDs shell, and thorough apparent kinetic analysis reveals that the photocatalytic hydrogen production process undergoes a Volmer-Heyrovsky mechanism that demonstrates the reduction reaction between photogenerated charges and water (H*+H2O+e-→H2↑+OH-), which is a critical missing investigation in photocatalytic studies for CPDs.