Jem 2100f tem instrument

The XRD patterns of the catalysts were obtained at room temperature on a PANalytical X'Pert Pro X-ray diffractometer at 40 kV and 40 mA over 20° to 80° 2θ range with Cu Kα radiation (λ = 0.15416 nm). N₂ adsorption–desorption isotherms for the catalysts were recorded on a Beckman coulter SA 3100 type specific surface area and aperture measurement instrument at −196 °C. The size distribution of micropores was determined using the Horvarth–Kawazoe(H–K) equation. The surface areas of the catalysts were calculated by the Brunauer–Emmett–Teller (BET) method. Transmission Electron Microscopy (TEM) images were recorded on a JEOL JEM-2100F TEM instrument at an accelerating voltage of 200 kV. The morphology of the catalyst was analyzed via scanning electron microscopy (SEM 450, Nova nano, Japan). The elemental chemical states of the samples were analyzed via X-ray photoelectron spectroscopy (XPS) using a Thermo Scientific Escalab 250Xi X-ray spectrometer with binding energy corrected by C 1s (284.8 eV). The basicity of the catalyst was measured by temperature-programmed desorption of CO₂ (CO₂-TPD) techniques on an AutoChem II 2910 instrument (Micromeritics, USA). The reduction behavior of the catalysts was studied via hydrogen programmed temperature-reduction (H₂-TPR) using a Micromeritics AutoChemII 2920 instrument equipped with a thermal conductivity detector (TCD).