Precursor-reforming strategy induced g-C₃N₄ microtubes with spatial anisotropic charge separation established by conquering hydrogen bond for enhanced photocatalytic H₂-production performance

Precursor-reforming strategy induced graphitic carbon nitride (g-C₃N₄) with different morphologies for enhanced photocatalytic hydrogen (H₂) evolution activity is highly desirable. Herein, g-C₃N₄ microtubes (mg-C₃N₄) with adjustable closure degree of microtube orifice and spatial anisotropic charge separation are established by conquering hydrogen bond during thermally exfoliate precursor. Compared to the bulk g-C₃N₄ (bg-C₃N₄) and ultrathin g-C₃N₄ (ug-C₃N₄), the tubular structure endows mg-C₃N₄ with spatial anisotropic charge separation that accelerates transfer of charge carriers. As expected, the photocatalytic H₂ evolution (PHE) activity of mg-C₃N₄ has been obviously enhanced. Particularly, the mg-C₃N₄-24 shows the best PHE activity (957.9 μmol h^-1 g^-1), which is over 18.72 and 3.77 times higher than the bg-C₃N₄ and ug-C₃N₄, respectively. In addition, selective photo-deposition experiment results reveal a charge carriers migration behavior that photoproduction electrons migrate to the outer shell and holes prefer to move onto the inner shell of mg-C₃N₄, thus achieving efficient spatial anisotropic charge separation. We firmly believe that the work presents significant advancement for the design of other materials by precursor-reforming strategy.