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Supporting Information

Electrospun vanadium sulfide / carbon hybrid fibers obtained via

one-step thermal sulfidation for use as lithium-ion battery electrodes

Samantha Husmann,1 Öznil Budak,1,2 Antje Quade,3 Anna Frank,4

Angela Kruth,3 Christina Scheu,4,5 Aura Tolosa,1 and Volker Presser1,2*

1 INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany

2 Saarland University, Campus D2 2, 66123, Saarbrücken, Germany

3 Leibniz Institute for Plasma Science and Technology, 17489 Greifswald, Germany

4 Max-Planck-Institut für Eisenforschung, Nanoanalytics and Interfaces, 40237 Düsseldorf, Germany

5 Materials Analytics, RWTH Aachen, 52074 Aachen, Germany

* Corresponding author’s e-mail: volker.presser@leibniz-inm.de

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Figure S1: Photograph of electrospun fibers treated at 300 °C for 30 min in Ar/H2 and then sulfidized

at 700 °C for 1 h.

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Figure S2: Scanning electron micrographs of the sulfidized fibers.

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Figure S3: (A) X-ray photoelectron survey spectra and (B) elemental fraction of sulfidized fibers.

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Figure S4: Initial cyclic voltammograms of the sulfidized fibers between 1.2 V and 3.5 V vs. Li/Li+

recorded with a sweep rate of 0.1 mV∙s-1.

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Figure S5: Initial cyclic voltammograms of the sulfidized fibers between 0.1 V and 1.2 V vs. Li/Li+

recorded with a sweep rate of 0.1 mV∙s-1.

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Figure S6: Coulombic efficiency of the rate handling profiles carried out between (A) 1.2 V and 3.5 V

vs. Li/Li+ and (B) 0.1 V and 3.0 V vs. Li/Li+.

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Figure S7: Cycling stability carried out between 1.2 V and 3.5 V vs. Li/Li+ at 1.0 A∙g-1.

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Figure S8: X-ray diffractograms of the fiber mat electrodes after rate handling testing carried out

between 0.1 V and 3.0 V vs. Li/Li+.

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Figure S9: Scanning electron micrographs of the 600-1h-2 (A,B) and 500-3h (C,D) fibers before (A,C)

and after (B,D) cycling between 0.2 V and 3.0 V vs. Li/Li+.

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Figure S10: Energy vs. Power charts of VSx fibers half-cells cycled at rates between 10 mA g-1 and 10 A

g-1 between (A) 1.2 V and 3.5 V vs. Li/Li+ and (B) 0.1 V and 1.2 V vs. Li/Li+.