Effect of Sn-doping on the electrochemical behaviour of TiO2 nanotubes as potential negative electrode materials for 3D Li-ion micro batteries

► Sn-doped TiO2 nanotubes were fabricated by anodization of sputtered Ti-Sn thin films. ► The Sn-doped TiO2nts can be used as anodes for 3D Li-ion micro batteries. ► The electrochemical performance of Sn-doped TiO2nts was better than simple TiO2nts. ► The improved performance is related to enhanced lithium diffusivity with Sn doping. ► This synthesis approach is extendable for Fe/Sb/Nb-doping of TiO2 nanotubes.