Su8020 ultra high resolution field emission scanning electron microscope

The X-ray diffraction (XRD) patterns were recorded on X’Pert–PRO, Panalytical, Almelo, The Netherlands, 2012 using Cu Kα radiation.
The N₂ sorption isotherms were measured at −196 °C using an ASAP Sorption Surface Area and Pore Size Analyzer (ASAP 2460, Micrometrics, Norcross, GA, USA 2018).
Scanning electron microscopy was performed with an SU8020 Ultra-High Resolution Field Emission Scanning Electron Microscope (Hitachi Ltd., Ibaraki, Japan, 2012). The elemental analysis was conducted using Energy-Dispersive X-ray spectrometers (EDX) with the same instrument. The samples for SEM were sputter-coated with 40 nm of chromium in order to reduce charging.
FT-IR spectra of the catalyst were obtained using a Thermo Finnigan Nicolet 380 FT-IR instrument with an ATR Smart iTX attachment (Thermo Fisher Scientific Inc., Waltham, MA, USA) in the wavenumber range from 490 to 4000 cm⁻¹.
Diffuse reflectance UV-Vis spectra of the catalyst in the wavelength range from 190 to 900 nm were obtained using a Jasco 650 (V-650, Jasco, Tokyo, Japan) spectrometer with a PIV-756 horizontal integrating sphere.

Sodium hydroxide, CuSO₄, 3,4-Dihydroxy-phenylalanine, and other metal ions were purchased from Sigma-Aldrich reagent company (Shanghai, China). N-2-hydroxyethylpiperazine-N-ethane-sulphonic acid (HEPES) was purchased from Aladdin chemistry company (Shanghai, China). All reagents were of analytical grade and used without further purification. Water was purified by a Milli-Q system. UV–vis absorbance spectrum measurements were performed on a PerkinElmer Lambda 750S UV–visible Spectrophotometer (PerkinElmer, Waltham, MA, USA). Fluorescent spectrum and lifetime were measured on a HORIBA Spectro fluorophotometer (Horiba, Kyoto, Japan). X-ray photoelectron spectroscopy (XPS) was conducted on a Thermo Fisher Scientific Escalab 250Xi photoelectron spectrometer (Thermo Fisher, Waltham, MA, USA). The scanning electron microscope images were captured on a SU8020 ultra-high resolution field emission scanning electron microscope (Hitachi, Tokyo, Japan).

The measurements for thin films were performed with the use of a high-resolution scanning electron microscope (SU8020 Ultra-High Resolution Field Emission Scanning Electron Microscope; Hitachi Ltd., Tokyo, Japan, 2012) equipped with a cold field electron emitter. The setup was screened against changes of magnetic field enabling high-quality ultra-high magnification of 200,000 times. The samples in the form of glass plates covered with thin metallic film were mounted over the sample holder with conductive carbon tape. Additionally, in order to avoid charging effects, the metal surface was connected to the ground, also with conductive carbon tape. A 5 kV accelerating voltage was applied for the SEM images.
The elemental composition of the thin metallic surfaces was characterized with an analyzer of X-ray photons emitted from the sample during electron bombardment. The Energy Dispersive Spectroscopy system (Thermo Scientific Ultra Dry, Pittsburgh, PA, USA) was applied. The samples were excited with 20 keV electrons during elemental analysis.