الفهرس 
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Abstract
from what has been discussed, one can arrive to the following conclusions:
1. A high activity of non-precious electrocatalyst has been successfully designed for replacement of the high-cost precious metal (Pt) in fuel cells.
2. The synthesized catalysts were prepared via electrospinning followed by stabilization at 240 oC and carbonization at 800 oC under an argon flow.
3. SEM photos show smooth,bead-free and continuous nanofibers (NFs)
with a nanoscale diameter.
4. TEM photos of the designed nanofibers after carbonization confirms that the metal nanoparticles are embedded in the carbon nanofibers (CNFs).
5. XRD analysis confirmed that the investigated M/NFs are free from oxides or hydroxides and also showed the formation of alloy structure for the Pd-Co-Mo/CNFs and Ni-Co-Mo/CNFs.
6. According to EDX analysis the Co/CNFs, Ni/CNFs, Ni-Zn/CNFs, Pd- Co-Mo/CNFs and Pd-Co-Mo/CNFs atomic weight ratio are found to be approximately as the started ratios.
7. The synthesized single and binary Co/NFs, Ni/CNFs and Ni-Zn/CNPs show improved electrocatalysis for methanol oxidation in an alkaline medium.
8. The electrochemical results show that the sample with 5 %wt. Co is preferable one for all methanol concentrations.
9. The behavior of activity with methanol for Co/CNFs and Ni/CNFs reveals that the optimum methanol concentration is 2 and 6 M, respectively.
10. The cyclic voltammogram (CV) profiles in the presence of methanol are totally different from KOH; a new redox peak appeared at different potential values, which indicates the electrooxidation of methanol.
11. Electrochemical measurements indicated that Pd-Co-Mo/CNFs and Ni- Co-Mo/CNFs possessed a good intrinsic activity towards ethanol oxidation compared to Pt/C.
12. from the results of Pd-Co-Mo/CNFs and Ni-Co-Mo/CNFs; in addition to the cost reduction; important outcomes can be observed due to the replacement of Pd by Ni in the catalyst systems: (i) enhancement of the electrocatalytic activity as the maximum current density significantly increased by 15 times. (ii) the optimum methanol concentration increased from 1 to 2 M which is a goal to reduce the volume of DMFCs.
13. For Pd-Co-Mo/CNFs and Ni-Co-Mo/CNFs, the optimum ethanol concentration was found to be 1 and 2 M, respectively.
14. Low cost, the good quality of the fiber, the high electrochemical activity and stability of the prepared catalysts for methanol and ethanol oxidation make them qualified for use as an alternative to Pt in fuel cell applications.