The electrocatalytic activities of Mn
3O
4/C composites are studied in lithium–oxygen (Li–O
2) batteries as cathode catalysts. The Mn
3O
4/C composites are fabricated using ultrasonic spray pyrolysis (USP) with organic surfactants as the carbon sources. The
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The electrocatalytic activities of Mn
3O
4/C composites are studied in lithium–oxygen (Li–O
2) batteries as cathode catalysts. The Mn
3O
4/C composites are fabricated using ultrasonic spray pyrolysis (USP) with organic surfactants as the carbon sources. The physical and electrochemical performance of the composites is characterized by X-ray diffraction, scanning electron microscopy, particle size analysis, Brunauer–Emmett–Teller (BET) measurements, elemental analysis, galvanostatic charge–discharge methods and rotating ring-disk electrode (RRDE) measurements. The electrochemical tests demonstrate that the Mn
3O
4/C composite that is prepared using Trition X-114 (TX114) surfactant has higher activity as a bi-functional catalyst and delivers better oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic performance in Li–O
2 batteries because there is a larger surface area and particles are homogeneous with a meso/macro porous structure. The rate constant (
kf) for the production of superoxide radical (O
2•−) and the propylene carbonate (PC)-electrolyte decomposition rate constant (
k) for M
3O
4/C and Super P electrodes are measured using RRDE experiments and analysis in the 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF
6)/PC electrolyte. The results show that TX114 has higher electrocatalytic activity for the first step of ORR to generate O
2•− and produces a faster PC-electrolyte decomposition rate.
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