Z-scheme electronic transfer of quantum-sized α-Fe2O3 modified g-C3N4 hybrids for enhanced photocatalytic hydrogen production

A quantum-sized hematite iron oxide (α-Fe 2 O 3 )/graphitic carbon nitride (g-C 3 N 4 ) hybrids have been designed and constructed through a facile in situ calcination treatment. The α-Fe 2 O 3 /g-C 3 N 4 hybrids were analyzed via various characterization techniques including XRD , TEM , UV–Vis DRS , XPS , and their photocatalytic efficiencies were evaluated by visible light-driven hydrogen evolution . The results reveal that the cooperation of α-Fe 2 O 3 and g-C 3 N 4 during fabrication process leads to synergy effects of not only the morphology but also the microstructure. These hybrids exhibit much higher hydrogen evolution efficiency than pure g-C 3 N 4 under visible-light illumination due to their improved light harvesting capability, enhancement of surface areas , predominant (110) facet exposure of α-Fe 2 O 3 as well as a prominent quantum size effect , and highly efficient electron transfer and separation. A proposed Z-scheme mechanism was further verified experimentally.