Wet chemical route to the synthesis of kesterite Cu2ZnSnS4 nanocrystals and their applications in lithium ion batteries

Sn-based quaternary material, Cu2ZnSnS4 (CZTS), was successfully synthesized using an inexpensive and quick wet chemical route. The obtained CZTS nanocrystals were characterized by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM) and selected area electron diffraction (SAED) techniques. XRD and SAED results revealed that kesterite CZTS was formed. The formed CZTS nanocrystals were slightly irregularly faceted particles with diameters between 5 nm and 25 nm. CZTS was studied as an anode material in rechargeable lithium ion battery for the first time. The Cu2ZnSnS4 annealed at 500 °C showed a capacity of about 540 mA h g−1 at the initial stage. The first cycle of the CZTS electrode exhibited enormously irreversible capacity. The result indicated that the formation of metallic Sn from the Cu2ZnSnS4 powder was similar to the case in SnO2 or SnS2 electrodes. Cu2ZnSnS4 was demonstrated to be one of the possible candidates of the anode materials for future lithium ion battery.

► Inexpensive and quick wet chemical route was used to synthesize the quaternary kesterite Cu2ZnSnS4.
► Nontoxic octadecylamine system was used as a solvent and a stabilizer in the synthesis process.
► Cu2ZnSnS4 has been studied as an anode material in the lithium ion batteries for the first time.