INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
Surface studies of lithium?oxygen redox reactions over HOPG
SANTIAGO HERRERA; CALVO EJ,; MARCHINI, F.; FEDERICO WILLIAMS
ELSEVIER SCIENCE BV
Lugar: Amsterdam; Año: 2016 vol. 646 p. 154 - 154
The O2/Li2O2 electrode reaction has been studied on lowsurface area HOPG electrodes in 0.1MLiPF6 in dimethyl sulfoxide (DMSO) electrolyte. Studieswere performed using electrochemical cells coupled to a XPS spectrometerand to an AFM microscope. AFM images after electrochemical treatment at cathodic potentials exhibited 20 to 100 nm in height features, whereas anodic treatment showed a thin film of about 1 nm thickness deposited over the HOPG electrode. XPS spectra after electrochemical treatment showed surface species due to DMSOand LiPF6 decomposition. These findings indicate the high reactivity of oxygen reduction products towards the electrolyte and the solvent. The unwanted deposits formed under electrochemical operation cannot be completely eliminated from the surface even after applying high anodic potentials. This highlights the known loss of capacity of Li-air batteries, issue that must be overcome for successful applications.