Icap 7000 series spectrometer

Scanning electron microscopy (SEM) was acquired in a secondary electron collection mode with an accelerating voltage of 5 KeV by using an APREO-S field emission scanning electron microscope (Thermo Fisher Scientific Inc., Waltham, MA, USA). Transmission electron microscopy (TEM) investigations were conducted on an accelerating voltage of 200 KeV on the JEM-F200 scanning transmission electron microscope (JEOL Ltd., Akishima, Tokyo, Japan). A ESCALAB X-ray photoelectron spectrometer (Thermo Fisher Scientific Inc., Waltham, MA, USA) was used for collecting X-ray photoelectron spectroscopy (XPS) data and all spectra were calibrated by aligning the C 1s peak at 284.8 eV. X-ray diffraction (XRD) patterns were obtained using a RIGAKU Miniflex X-ray diffractometer (Applied Rigaku Technologies, Inc., Akishima, Tokyo, Japan), with Cu-Kα radiation, at a scan rate of 5° per minute. Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis was performed on an iCAP 7000 Series spectrometer (Thermo Fisher Scientific Inc., Waltham, MA, USA) to assess the possible dissolution of the catalyst component after the prolonged electrochemical stability test. For the analysis, 2 mL of the electrolyte was taken and then acidified using 4 mL of 1 M HCl. The solution was further filtered through a 0.22 μm nylon filter before being sent for the ICP-AES test.