Fabrication and evaluation of Co-NC electrocatalyst as an oxygen reduction reaction electrocatalyst for use in Al-Air

Energy production and related fields are currently one of the most important and challenging issues. Aluminum-air batteries have attracted the attention of researchers and industrial activists due to their high capacity, energy and economic efficiency. The performance of aluminum-air batteries is fundamentally dependent on the oxygen reduction reaction at the cathode side. Catalysts based on noble metals such as platinum have been widely used in the cathode of these types of batteries for ORR. The high cost of platinum catalysts has drawn attention to carbon catalysts doped with heteroatoms and inexpensive metals. Based on the research done in recent years, M-N-C catalysts have shown good performance for ORR. Considering the unique characteristics of organic-metallic frameworks, such as high surface area, etc., in this research, the effort is to make cathode based on organic-metallic frameworks that have suitable efficiency for the oxygen reduction reaction. Therefore, it has been tried to prepare organic-metallic frameworks with suitable surface area by using nitrogen-containing ligands which boosts conductivity such as ۲-methyl imidazole. Then, M- N-C catalysts has been prepared by performing the pyrolysis process. In the next step, the properties of the prepared electrocatalysts for the oxygen reduction reaction were tested in the three-electrode testing system. The aim of this research is to synthesize electrocatalysts based on metal-organic frameworks comparable to commercial Pt/C known as the best electrocatalysts used in the cathode of aluminum- air batteries. Electrocatalysts based on metals such as Co have shown promising performance regarding their electrical conductivity .in the first attempt Co-NC electrocatalysts based on metal-organic frameworks have been synthesized through pyrolysis. Then the conductivity of this electrocatalyst has been compared to the commercial Pt/C in O۲ saturated ۰.۱ M KOH. Cyclic voltammetry and linear sweep voltammetry data are shown in the figures below. E onset and halfwave potential of synthesized Co-NC electrocatalyst in ۱۶۰۰ rpm was ۰.۸۷ VRHE and ۰.۷۷ V RHE respectively.

کلیدواژه ها:

Aluminum- air batteries ، Metal-organic framework ، Oxygen reduction reaction ، Co-NC