2.3 Characterization
X-ray Diffraction measurement of the obtained samples was carried out by an advanced diffractometer operating (HORIBA Scientific, France; 40 kV and 30 mA ). SEM (Zeiss evo10) were used to obtain the morphology information about the samples. TEM: FEI Tecnai TF20 high-resolution transmission electron microscope. XPS testing was performed on an energy dispersive X-ray instrument (ESCALAB 250Xi) using energy dispersive X-ray analysis. UV-vis diffuse reflectance spectra were tested on a PerkinElmer Lambda-750 UV-vis-near-IRvia spectrometer using BaSO4 as a reference for baseline correction. The N2 adsorption-desorption isotherm of the sample was obtained at 77K using ASAP2020M. The PL spectrum were acquired by a FLUOROMAX-4 spectrophotometer at room temperature. Na2SO4 (0.2 M) aqueous solution was used as supporting electrolyte. In a standard three-electrode cell, the photoelectrochemical measurement was performed on an electrochemical analyzer (VersaStat4-400, Advanced measurement Technology, Inc).