Hydrothermal supramolecular preorganization synthesis of multi-morphological g-C3N4/Fe2O3 for photocatalytic removal of indoor formaldehyde under visible light

In this study, multi-morphological g-C 3 N 4 / Fe 2 O 3 were prepared via hydrothermal supramolecular preorganization for the removal of formaldehyde in simulated indoor environments . We synthesized bulk, spherical and tubular g-C 3 N 4 under hydrothermal conditions and subsequently attached Fe 2 O 3 nanoparticles by impregnation method. Tubular g-C 3 N 4 /Fe 2 O 3 (27.46 m 2 /g) and spherical g-C 3 N 4 /Fe 2 O 3 (33.50 m 2 /g) synthesized through hydrothermal supramolecular preorganization method possessed the higher specific surface area than bulk g-C 3 N 4 /Fe 2 O 3 (11.05 m 2 /g). Among three morphologies of g-C 3 N 4 /Fe 2 O 3 , tubular g-C 3 N 4 /Fe 2 O 3 exhibited the best performance (65%) than bulk (41%) and spherical (59%) and possessed favorable stability. In addition, we explored and optimized the effects of different indoor simulation conditions (formaldehyde concentration, relative humidity, light source power) on the photocatalytic removal of formaldehyde. The mechanism was proposed that g-C 3 N 4 /Fe 2 O 3 formed Z-type heterojunction to promote the separation of photo-generated electrons and holes, further generating hydroxyl radical and superoxide radical to oxidize formaldehyde.