*2.3. Characterizations*

The morphology and principle of the products were characterized by field-emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDX) on a JEOL (JSM-7600F) and Oxford instrominis (X-Max). The crystalline phase compositions of the samples were characterized by X-ray diffraction (XRD) on a D8 Advance (TRIO/TWIN) X-ray diffractometer. The specific surface area, pore diameter, and volume were obtained using Brunauer, Emmett, Teller (BET, BELSORPmini II) involving N2 gas adsorption/desorption isotherms analysis. The properties of the interface were analyzed by X-ray photoelectron spectroscopy (XPS) on the Thermo ESCALAB 250.
