Highly stable nanostructured Bi2Se3 anode material for all solid-state lithium-ion batteries

The electrochemical reaction mechanism of lithium (Li)-ion with Bi2Se3 anode material in all solid-state lithium-ion batteries (LIBs) has been successfully established in this work. Firstly, commercial bulk Bi2Se3 was directly used as anode in LIB and then hydrothermally synthesized Bi2Se3 nanostructures were used as anode material in order to improve the electrochemical performance of the battery. The structure of obtained nanostructures was characterized using powder x-ray diffraction, which verified the formation of Bi2Se3 phase. Scanning electron microscopy and transmission electron microscopy studies confirmed the existence of mixed morphology, i.e., nanoparticles and nanosheets, with the diameter of nanoparticles in the range of 20–150 nm and the thickness of nanosheets, about 5–30 nm. Furthermore, electrochemical measurements indicated the initial discharge and charge capacity of bulk Bi2Se3 as 621 mAhg−1 and 499 mAhg−1 respectively, which was slightly higher than the Bi2Se3 nanostructures (discharge and charge capacities: 594 mAhg−1 and 468 mAhg−1). However, the nanostructures showed better cycling stability up to 50 cycles as compared to the bulk, which shed light on a new way to improve the lithium storage properties of the Bi2Se3.