title: Surface modification of battery electrodes via electroless deposition with improved performance for Na-ion batteries.
abstract: Sodium-ion batteries (SIBs) are emerging as potential stationary energy storage devices due to the abundance and low cost of sodium. A simple and energy efficient strategy to develop electrodes for SIBs with a high charge/discharge rate is highly desirable. Here we demonstrate that by surface modification of Ge, using electroless deposition in SbCl3/ionic liquids, the stability and performance of the anode can be improved. This is due to the formation of GexSb1-x at the surface leading to better diffusion of Na, and the formation of a stable twin organic and inorganic SEI which protects the electrode. By judicious control of the surface modification, an improvement in the capacity to between 50% and 300% has been achieved at high current densities (0.83-8.4 A g(-1)) in an ionic liquid electrolyte NaFSI-[Py1,4]FSI. The results clearly demonstrate that an electroless deposition based surface modification strategy in ionic liquids offers exciting opportunities in developing superior energy storage devices.
authors.affiliation: Institute of Electrochemistry, Clausthal University of Technology, Arnold-Sommerfeld-Str. 6, 38678, Clausthal-Zellerfeld, Germany. abhishek.lahiri@tu-clausthal.de frank.endres@tu-clausthal.de.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Lahiri
authors.affiliation: Institute of Electrochemistry, Clausthal University of Technology, Arnold-Sommerfeld-Str. 6, 38678, Clausthal-Zellerfeld, Germany. abhishek.lahiri@tu-clausthal.de frank.endres@tu-clausthal.de.
authors.forename: Mark
authors.initials: M
authors.lastname: Olschewski
authors.affiliation: Institute of Electrochemistry, Clausthal University of Technology, Arnold-Sommerfeld-Str. 6, 38678, Clausthal-Zellerfeld, Germany. abhishek.lahiri@tu-clausthal.de frank.endres@tu-clausthal.de.
authors.forename: René
authors.initials: R
authors.lastname: Gustus
authors.affiliation: Institute of Electrochemistry, Clausthal University of Technology, Arnold-Sommerfeld-Str. 6, 38678, Clausthal-Zellerfeld, Germany. abhishek.lahiri@tu-clausthal.de frank.endres@tu-clausthal.de.
authors.forename: Natalia
authors.initials: N
authors.lastname: Borisenko
authors.affiliation: Institute of Electrochemistry, Clausthal University of Technology, Arnold-Sommerfeld-Str. 6, 38678, Clausthal-Zellerfeld, Germany. abhishek.lahiri@tu-clausthal.de frank.endres@tu-clausthal.de.
authors.forename: Frank
authors.initials: F
authors.lastname: Endres