A well-engineered two-dimensional coral-like architecture CNWO3 for the effective removal of volatile organic compounds from indoor air

Abstract

One of the promising strategies to enhance the photocatalytic performance of graphitic carbon nitride (CN) is to establish 2D photocatalysts with boosted morphology and adjusted charge transfer direction. Herein, a green and sustainable strategy (water used as solvent) is employed to fabricate a coral-like CNWO3 with highly desirable visible-light photocatalytic activity. The coral-like structure provides more atoms at the edges and corners to act as active antennae to enhance the photocatalytic activity. These new antennae generate various active sites that are short enough to drive strong visible light harvesting, while being large enough to prevent intense quantum confinement effects. Under visible-light irradiation (λ > 400 nm), the as-prepared photocatalyst effectively removes gaseous acetaldehyde (90.5 %) and toluene (73.4 %), the two most common volatile organic compounds (VOCs) in indoor air, possibly due to its unique structure. The DFT calculations clearly show that the interaction of acetaldehyde and toluene over CNWO3 is energetically more favorable than that over CN. Both the hydroxyl (OH) and superoxide (O2−) that are generated by the photocatalyst play a substantial role in VOCs degradation. This work highlights the solar-active photocatalysis development using a synergy of morphology and material nature for sophisticated gas-phase reactions to effectively solve VOCs pollution issues of the indoor environment.