Self-Assembled Cu–Sn–S Nanotubes with High (De)Lithiation Performance

Through a gelation–solvothermal method without heteroadditives, Cu–Sn–S composites self-assemble to form nanotubes, sub-nanotubes, and nanoparticles. The nanotubes with a Cu3–4SnS4 core and Cu2SnS3 shell can tolerate long cycles of expansion/contraction upon lithiation/delithiation, retaining a charge capacity of 774 mAh g–1 after 200 cycles with a high initial Coulombic efficiency of 82.5%. The importance of the Cu component for mitigation of the volume expansion and structural evolution upon lithiation is informed by density functional theory calculations. The self-generated template and calculated results can inspire the design of analogous Cu–M–S (M = metal) nanotubes for lithium batteries or other energy storage systems.