X-ray diffraction (XRD) patterns were observed on a Rigaku
Dmax X-ray diffractometer using Cu K radiation. BET surface area
was measured onASAP2020 using N2 adsorption at −196 ◦C. Raman
spectra were recorded on a Renishaw inVia Raman microscope
using an excitation of 632 nm laser light. Transmission electron
microscopy (TEM) images were obtained on a JEM-100CX electron
microscope.XPS spectra were obtained by aVGMultilab 2000X-ray
photoelectron spectrometer using Mg K radiation, and calibrated
by referencing the binding energy to adventitious carbon (C1s
284.6 eV). Diffuse reflectance UV–vis–IR (DRUV–vis–IR) absorption
spectra were recorded on a UV-3600 spectrophotometer. Photoluminescence
spectra (PL) were recorded at room temperature on a
QM/TM/NIR spectrofluorometer (PTI) by using 337 nm and 480 nm
excitation light.