Colloidal hot injection synthesis of Cu₂FeSnS₄ nanoparticles towards an enhanced capacity anode material for Li-ion batteries

The increasing demand for portable energy storage devices has prompted a considerable exploration into advanced anode material with higher Li-ion battery capacities. Quaternary chalcopyrite semiconductors have generated significant attention as promising materials in applications such as optoelectronic devices, energy conversion, and energy storage devices. In this paper, Cu₂FeSnS₄ (CFTS) nanoparticles were prepared through a colloidal hot injection method (HIM). The structural analysis indicates that the CFTS nanoparticles exhibit a pure tetragonal structure characterized by high crystallinity. The morphological and elemental analysis shows the stoichiometric synthesis of CFTS nanoparticles with significant agglomeration of crystallites, accompanied by variation in size. The CFTS nanoparticles, employed as an anode material for Li-ion batteries, demonstrated significant performance characterized by high reversible capacity and stability at ambient temperature. The initial discharge capacity is achieved at 1181 mAhg⁻¹ and retains 528 mAhg⁻¹ during charge-discharge cycles within the voltage range of 0.005 to 3.0 V (versus Li/Li+) after 5 cycles. The CFTS nanoparticle performance findings indicate its promising implementation as an anode electrode in Li-ion batteries.