Searching for a non-noble metal electrocatalyst that could efficiently catalyze oxygen reduction reaction (ORR) in alkaline solutions is of great importance for improving the performance and costs of alkaline fuel cells and metal-air batteries. In this work, copper oxide (Cu2O) nanostructures were obtained via an electrochemical transformation of a copper dithioxamide Cu(dto) chelate polymer in 1 M KOH solution. To improve conductivity and dispersion of Cu2O, the electrochemical transformation took place in the acetylene black matrix. The resultant Cu2O/C nanocomposite was grown on a glassy carbon electrode and its electrocatalytic activity towards ORR in 1 M KOH was studied using cyclic voltammetry (CV) and rotating disk electrode (RDE) linear sweep voltammetry (LSV). The ORR activity was observed in O2-saturated KOH solutions. The value of the half-wave potential (E1/2) was estimated to be 0.72 V vs. RHE, which is close to the E1/2 value of the benchmark 40 % Pt/C catalysts. The electron transfer number, n, was found to be 3, suggesting that in addition to the direct 4e− reduction process, the 2e− reduction processes also occur, mostly on the carbon matrix. The results indicate that the Cu(dto)-derived Cu2O/C nanocomposite may provide a cost-effective alternative to noble metals ORR electrocatalyst due to its better mass activity and stability in alkaline solutions.
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