2.3 Material Characterization
The morphology of the synthesized materials was investigated by a field emission scanning electron microscope (SEM, Hitachi SU8100, Japan) and a field emission transmission electron microscope (TEM, FEI Tecnai G2 F20 S-TWIN, USA). Meanwhile, the chemical composition ZMOP-x was tested by energy dispersive spectrometer (EDS). The crystal structure of the as-prepared materials was studied by X-ray diffractometer (XRD, D/max2200PC, Cu Kα radiation = 1.5406 Å, Japan). All data were tested with 2θ values ranging from 10° to 70° with 2°/min scan rate. X-ray photoelectron spectroscopy (XPS, ESCALAB 250X, USA) was utilized to ascertain the elemental type and valence states within the samples. The Fourier transform infrared spectroscopy (FTIR) was used to analyze the molecular framework of the materials.