High-temperature (HT) LiCoO2 recycled from spent lithium ion batteries as catalyst for oxygen evolution reaction.

Graphical abstract HT LiCoO 2 synthesized using the cathodes of LIBs as raw materials as catalyst for OER. Highlights • Thermal synthesis of HT LiCoO 2 from Co(OH) 2 recycled from spent Li-ion batteries. • HT LiCoO 2 is used as an electrocatalyst for the oxygen evolution reaction. • Cyclic voltammetry and chronoamperometry tests of HT LiCoO 2 for OER. • The activation free energy of the reaction of OER. Abstract Development of novel materials based on inexpensive metals is crucial for renewable energy storage technologies. Furthermore, the recycling of compounds, such as lithium cobaltate (LiCoO 2) from Li-ion battery cathodes, contributes to the recovery of important elements, such as Co and Li. The applicability of high-temperature (HT) LiCoO 2 as a multifunctional material has been tested. In this work, HT LiCoO 2 is used as an electrocatalyst for the oxygen evolution reaction (OER). Cyclic voltammetry and chronoamperometry tests show that the evolution of oxygen starts at 0.35 V accompanied by the formation of Co4+ ions. The activation free energy of the reaction calculated using Tafel plot is 28.0 kJ mol−1 and electrochemical impedance spectroscopy elucidates an equivalent circuit with a transfer charge resistance of 1.55 Ω, Warburg impedance of 150.3 Ω, and constant phase elements of 3.50 and 1.35 m F inside the pores and at the double layer, respectively. [ABSTRACT FROM AUTHOR]