X ray diffractometer model ttr 3

The repeated XRD analysis at various synthesis steps such as Nafion-CEL, pre-PANI shield, catalyst layer and the shielded catalytic layer was performed at Rigaku X-ray diffractometer model TTR-III (Tokyo, Japan) with Cu Kα radiation over a range of 2θ degree of 10–80 at a scan rate of 10° min⁻¹. The XRD spectra were carefully analysed with a materials data analysis software, MDI Jade.

The morphology of the nanoparticles was characterized using a field emission scanning electron microscope (FESEM, Gemini 500, Germany). The chemical composition of the nanoparticles was investigated using Fourier transform infrared spectrometer (FTIR, Thermo Nicolet FTIR spectrometer, USA). Powder X-ray diffraction (PXRD) patterns were obtained using a Rigaku X-ray Diffractometer Model TTR-III (Tokyo, Japan). TGA thermograms were recorded using a TGA Q5000 V3.15 analyzer at a heating rate of 10 °C min⁻¹ under N₂ atmosphere. Brunauer–Emmett–Teller (BET) gas sorptometry measurements were performed on an Autosorb iQ (Quantachrome, Autosorb iQ, USA) at 77 K. Before each isotherm, approximately 200 mg of activated MOF samples was activated by heating for 5 h under high vacuum at 120 °C. Element analysis (EA) was tested by Elementar (Vario EL/micro cube, Germany).