Electrochemical Behaviour of Nb-Doped Anatase TiO2 Microbeads in an Ionic Liquid Electrolyte
Journal article, 2020

TiO(2)is a promising material for high-power battery and supercapacitor applications. However, in general TiO(2)suffers from an initial irreversible capacity that limits its use in different applications. A combination of a microbead morphology, Nb-doping, and the use of an ionic liquid electrolyte is shown to significantly decrease the irreversible capacity loss. A change in the electrochemical response in the first cycles indicates formation of a solid-electrolyte interphase (SEI) or a modification of the structure of the surface layer of the TiO2/Nb microbeads, which apparently stabilises the performance. The change in the response is manifested in an increased charge transfer resistance and the presence of two charge transfer contributions. During prolonged cycling the TiO2/Nb electrode shows an excellent stability over 5000 cycles. Ex situ analysis after cycling shows that the overall microbead morphology is intact and that there are no changes in the crystal structure. However, a decrease in the intensity of the XRD pattern can point to a decrease in size of the nanocrystals building up the microbeads or the formation of amorphous phases.

ionic liquid

TiO2

supercapacitor

Nb-doping

improved stability

Author

Simon Lindberg

Chalmers, Physics, Materials Physics

Carmen Cavallo

Chalmers, Physics, Materials Physics

University of Oslo

Giulio Calcagno

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Adriana Navarro Suárez

Chalmers, Physics, Materials Physics

Patrik Johansson

Chalmers, Physics, Materials Physics

Aleksandar Matic

Chalmers, Physics, Materials Physics

BATTERIES & SUPERCAPS

2566-6223 (eISSN)

Vol. 3 11 1233-1238

STARC (Sulfur Technology Advanced Research Concept)

Swedish Energy Agency, 2017-02-21 -- 2020-01-01.

Highly Concentrated Electrolytes: Cell Optimisation and Fundamentals

Swedish Energy Agency, 2014-10-01 -- 2018-09-30.

Subject Categories

Inorganic Chemistry

Materials Chemistry

Other Chemical Engineering

DOI

10.1002/batt.202000076

More information

Latest update

11/5/2020