Interfacial sodium storage in NaF–Ti nanocomposites

A heterogeneous nanocomposite material of NaF–Ti thin film is prepared by pulsed laser deposition and its interfacial sodium storage behavior is investigated for the first time. The nanocomposite NaF–Ti exhibits a much higher reversible discharge capacity than that of either a pure NaF or a pure Ti electrode. The sodium chemical diffusion coefficients in NaF–Ti nanocomposites are approximately estimated to be in the range from 6.5 to 46.4 × 10− 15 cm2 s− 1 by potential step measurements.

► In this paper, we fabricated a nanocomposite NaF–Ti thin film by pulsed laser deposition.
► We examined its electrochemical behaviors with sodium.
► NaF–Ti exhibited a higher reversible discharge capacity than that of a pure NaF or a pure Ti electrode.
► Our results have initially demonstrated the possibility of the interfacial sodium storage in SIB.