2.4 Characterization of nanosheets and lamellar membranes
The structure and morphology of MOF nanosheets and hierarchical MOF lamellar membranes were characterized by X-ray diffraction (XRD, RigakuD/max2500 v/Pc), N2 absorption and desorption (Quantachrome Ltd., America), atomic force microscopy (AFM, Bruker Dimension FastScan), scanning electron microscope (SEM, Auriga FIB SEM, Zeiss, Germany), and high-resolution transmission electron microscopy (HRTEM, Tecnai G2 F20, FEI, U.S.). The chemical properties were analyzed by X-ray photoelectron spectroscopy (XPS, AXIS Supra, Kratos, UK) and fourier transform infrared spectroscopy (FTIR, Nicolet MANGNA-IR560). The wettability and dynamic contact angle were probed by FACE (model OCA 25, Germany).