2026-04-17T20:48:05Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/113772026-02-18T01:05:43Zcom_10259_5822com_10259_5086com_10259_2604col_10259_5823

Solid Electrolyte Interphase (SEI) at TiO2 Electrodes in Li-Ion Batteries: Defining Apparent and Effective SEI Based on Evidence from X-ray Photoemission Spectroscopy and Scanning Electrochemical Microscopy Ventosa Arbaizar, Edgar Madej, Edyta Zampardi, Giorgia Mei, Bastian Weide, Philipp Antoni, Hendrik La Mantia, Fabio Muhler, Martin Schuhmann, Wolfgang Li-on batteries Solid electrolyte interphase X-ray photoemission Scanning electrochemical microscopy Titanium dioxide Química Química analítica Chemistry Chemistry, Analytic The high (de)lithiation potential of TiO2 (ca. 1.7 V vs Li/Li+ in 1 M Li+) decreases the voltage and, thus, the energy density of a corresponding Li-ion battery. On the other hand, it offers several advantages such as the (de)lithiation potential far from lithium deposition or absence of a solid electrolyte interphase (SEI). The latter is currently under controversial debate as several studies reported the presence of a SEI when operating TiO2 electrodes at potentials above 1.0 V vs Li/Li+. We investigate the formation of a SEI at anatase TiO2 electrodes by means of X-ray photoemission spectroscopy (XPS) and scanning electrochemical microscopy (SECM). The investigations were performed in different potential ranges, namely, during storage (without external polarization), between 3.0–2.0 V and 3.0–1.0 V vs Li/Li+, respectively. No SEI is formed when a completely dried and residues-free TiO2 electrode is cycled between 3.0 and 2.0 V vs Li/Li+. A SEI is detected by XPS in the case of samples stored for 6 weeks or cycled between 3.0 and 1.0 V vs Li/Li+. With use of SECM, it is verified that this SEI does not possess the electrically insulating character as expected for a “classic” SEI. Therefore, we propose the term apparent SEI for TiO2 electrodes to differentiate it from the protecting and effective SEI formed at graphite electrodes. Financial support from the DFG (Deutsche Forschungsgemeinschaft) in the framework of the Cluster of Excellence RESOLV (EXC1069) is gratefully acknowledged. 2026-02-17T09:28:56Z 2026-02-17T09:28:56Z 2016-12 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion 1944-8244 https://hdl.handle.net/10259/11377 10.1021/acsami.6b13306 1944-8252 eng ACS Applied Materials & Interfaces. 2016, V. 9, n. 3, p. 3123-3130 https://doi.org/10.1021/acsami.6b13306 info:eu-repo/semantics/openAccess application/pdf American Chemical Society