K alpha x ray photoelectron spectroscopy

FTIR spectroscopy was carried out on a Spectrum Two Spectrometer operating at a resolution of 4 cm⁻¹ over 4000–450 cm⁻¹; the sample for FTIR spectroscopy was lyophilized and ground with KBr to prepare KBr pellets.
TEM was performed on a JEOL JEM-2100F transmission electron microscope. The suspension was spotted on formvar-coated Ni or Cu grids, and the samples on Ni or Cu grids were then dried under vacuum.
XPS was performed using K-Alpha X-ray photoelectron spectroscopy (Thermo Fisher Scientific, USA). Binding energies were referenced to the C 1s line at 284.8 eV from adventitious carbon. The samples for XPS were re-dissolved with deionized water three times to get rid of the unattached Mb–Cu molecules.
ICP-AES was performed on an Agilent ICP-OES 730 Spectrometer operating with a plasma gas flow of 15 L/min, an auxiliary gas flow of 1.5 L/min, and an atomizing gas pressure of 200 kPa. The sample for ICP-AES was dissolved in double-distilled water and lyophilized.

The crystal structure of samples was analyzed by a Bruker D8 DISCOVER X-ray diffractometer (XRD). UV-Raman spectra were recorded on a Jobin-Yvon T64000 triple-stage spectrograph with spectral resolution of 2 cm⁻¹. The thermal behavior of the GaOOH nanorod was investigated by thermal gravimetric analyzer (Pyris1 TGA). For the morphological and microstructural analysis, a Hitachi S-4800 field-emission scanning electron microscope (SEM) equipped and a JEOL JEM-2100 transmission electron microscopy (TEM) were utilized. The ultraviolet-visible (UV-vis) absorption spectra were taken using a Hitachi U-3900 UV-vis spectrophotometer. The chemical composition of samples was characterized by a Thermo Scientific K-Alpha X-ray photoelectron spectroscopy (XPS).

Information about the microscopic topography of the photocatalyst was obtained from the scanning electron microscope (SEM) images by using a Hitachi SU8010 SEM. The microstructure was characterized by the FEI-TALOS-F200X transmission electron microscope (TEM). From the Fourier transform infrared spectrometer (FTIR-650), information about the functional groups carried by the catalyst were obtained. The test wavelength range is set from 4000 to 400 cm⁻¹. An Ultima IV X-ray diffractometer (XRD) was used to analyze the structure of the samples. The element properties were studied by Thermo Scientific K-alpha+X-ray photoelectron spectroscopy (XPS). PerkinElmer and LAMADA950 ultraviolet–visible spectroscopy (UV-vis) provided UV absorption spectra and UV diffuse reflectance spectra. The ultraviolet diffuse reflectance spectroscopy (UV-vis DRS) displayed information about the light absorption by photocatalysts. Steady-state, transient fluorescence spectra of samples were obtained with a Hitachi F-4600 photometer. The Mott–Schottky curve, photocurrent response, and Electrochemical Impedance Spectroscopy (EIS) Nyquist plot were measured on an electrochemical workstation (CHI760E).

The prepared nanopigments were characterized physiochemically using the following techniques and methods: The purity formed phases, and crystallite sizes of Ag@TiO₂-modified nanopigments were studied by X-ray powder diffraction (D/Max 2500 PC, Rigaku, Japan) using Cu target operating at 40 kV and 100 mA (with a scan speed of 4°/min) and Cu-Kα radiation of wavelength equals 1.54059 Å. The diffraction angle 2θ was scanned in the range 10°–80°. The morphology of the particles was characterized by a transmission electron microscope (TEM, JEM-2100, Japan) operated at 200 kV. Samples for TEM investigation were prepared by placing a drop of sonicated colloidal dispersion on the carbon-coated copper grid and then allowing the drops to dry in the air. The valence state and elemental composition of the prepared samples was characterized using a Thermo Scientific K-Alpha X-ray photoelectron spectroscopy (XPS) operated with an Al-Kα micro-focused monochromator within an energy range up to 4 keV. UV–Vis spectrum was recorded at room temperature using a spectrophotometer (UV–Vis, JASCO V-570, Japan). Photoluminescence (PL) spectra are collected at excitation wavelength of 320 nm using a luminescence spectrometer (Varian-CARY Fluorospectrophotometer).