Fig. 2: Characterization of nanosheets and Cu-TCPP lamellar membranes.

a UV-Vis spectra of H2TCPP and Cu-TCPP. The schematic diagram showed the replacement of hydrogen atoms by copper atoms in H2TCPP to form Cu-TCPP. b FT-IR spectra of Cu-TCPP and H2TCPP. c Image of prepared nanosheet in ethanol dispersions. d AFM image of individual Cu-TCPP nanosheet. The scanning direction is the direction of the arrow in the image. Scale bar, 3 μm. e Zeta potential of Cu-TCPP nanosheet dispersions versus pH value. f TEM images of Cu-TCPP nanosheets and the corresponding elemental mapping images of C, N, and O. Scale bar is 200 nm for HAADF image and 1 μm for other images. g Optical image and flexibility demonstration of Cu-TCPP membrane. h SEM image of the cross-sectional morphology of the Cu-TCPP membrane. Scale bar, 10 μm (Left). Scale bar, 2 μm (Right).