One-step access to bifunctional gamma-Fe2O3/8-FeOOH electrocatalyst for oxygen reduction reaction and acetaminophen sensing

Background: Design of advanced materials for multifunctional applications in catalysis is a new and promising research direction to ensure sustainable development.Method: An electrochemical method using pulse alternating current has been applied for the one-step and environmentally benign design of gamma-Fe2O3/8-FeOOH bifunctional electrocatalyst for oxygen reduction reaction and environmental pollutant detection. Significant findings: The finding gamma-Fe2O3/8-FeOOH nanocomposite can be regarded as an effective catalyst to enhance electrocatalytic activity toward ORR and acetaminophen (paracetamol) drug detection. The gamma-Fe2O3/ 8-FeOOH sensor achieved an excellent analytical performance for amperometric determination of acetamino-phen with a wide concentration range (0.05 -100 mu M), low detection limit (30 nM), outstanding long-term stability and high selectivity in the presence of various interfering reagents. In addition, the modified elec-trode demonstrated high electrocatalytic activity and good durability in alkaline medium for the oxygen reduction reaction. Therefore, gamma-Fe2O3/8-FeOOH revealed the superior performance due to the synergistic effect between the phases in the iron-based catalyst. The electrosynthesis using pulse alternating current holds great promise for the development of the mixed-phased catalysts for multifunctional applications.