Tecnai g2 f20 s twin high

Transmission electron microscopic (TEM) images were performed using a FEI Tecnai G2 F20 S-TWIN high-resolution transmission electron microscope operating at 200 kV. Atomic force microscopy (AFM, SPM-9600, Shi-madzu, Japan) images were obtained on a Si substrate. The Zeta potential were determined by a Malvern Zeta Sizer (Malvern, NanoZS, UK). Fourier transform infrared (FTIR) spectra were recorded on a Nicolet 6700 FTIR spectrometer (Thermo Fisher Scientific, USA). Raman spectra were taken with a LabRAM HR-800 micro spectrometer system equipped with a 514.5 nm Arþ laser. UV-Vis spectra were performed by a UV-Vis spectrometer (Lambda 35, PerkineElmer, USA). The platinum contents were measured by inductively coupled plasma-optical emission spectroscopy (ICP-OES, Arcos, Germany).

Pt NPs, Pd NPs, PdCu nano-alloy, Ag-Cu₂O nanocomposite, Ag, Cu₂O, transition metal oxides (TMO) NPs and the catalyst samples were characterized by powder X-ray diffraction (Bruker D8-advance X-ray powder diffractometer (Cu Kα, λ=1.5406 Å)), transmission electron microscope (TEM, Hitachi model H-800), HRTEM (recorded by a FEI Tecnai G2 F20 S-Twin high-resolution transmission electron microscope working at 200 kV and a FEI Titan 80–300 transmission electron microscope equipped with a spherical aberration (Cs) corrector for the objective lens working at 300 kV), and scanning electron microscope (JSM-6301F). XPS were recorded on a VG EscaLab 220i-XL spectrometer using a standard Al Kα X-ray source (300 W) and an analyzer pass energy of 20 eV. All binding energies were referenced to the adventitious C1s line at
284.9 eV. Specific surface area was determined from N₂ adsorption isotherm at −196 °C using standard Brunauer–Emmett–Teller (BET) theory. Before the measurement of N₂ adsorption, degassing was conducted at 300 °C for 4 h. The catalyst loadings were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) on a Thermo Scientific iCAP 6300 ICP spectrometer.