Enhanced visible-light-driven photocatalytic removal of NO: Effect on layer distortion on g-C₃N₄ by H₂ heating

We report a simple strategy for realizing the tunable structure distortion of graphitic carbon nitride (g-C₃N₄) layers by H₂ post calcination to improve the intrinsic electronic structure and the photocatalytic performances of g-C₃N₄ samples. In comparison with the O₂ or N₂ post treatment, the H₂-modified g-C₃N₄ develops new optical absorption above 460 nm and enhances photocatalytic activity for NO removal. The combined characterization results reveal that H₂ heating induced the structure distortion of g-C₃N₄ layers is originated from the creation of amino groups within the structure and generation of the strong hydrogen bonding interactions between layers. The distorted structure allows n–π* electron transitions in g-C₃N₄ to increase visible-light absorption. The structure distortion also enables more electrons to be available for initiating the photocatalytic reaction and the separation of photogenerated charge carriers in g-C₃N₄. This work provides a simple strategy for realizing the tunable structure distortion of g-C₃N₄ layers to adjust its electronic structure and photocatalysis. Copyright © 2015 Elsevier B.V.