Stacking surface derived catalytic capability and by-product prevention for high efficient two dimensional Bi2Te3 cathode catalyst in Li-oxygen batteries.

Various two-dimensional (2D) structures cause different catalytic anisotropy based on the stack layers in Li-oxygen batteries (LOBs). Clarify the key factor for catalytic performance of 2D materials in LOBs is necessary. In this study, 2D structured Bi 2 Te 3 with five Te-Bi atom layers in its stack layers is applied as the cathode catalyst for LOBs. Hexagonal nanodisks and roller-like nanoparticles are prepared for exposed controlling crystal plane by simple one-step hydrothermal method. It reveals the stack surface (001) plane can provide outstanding catalytic capability with high conductivity after the adsorption of discharge products and efficient pathway for the conversion from LiO 2 to Li 2 O 2 and prevent the formation of by-products. As consequence, a superior specific capacity of 21,172 mAh g−1 and high cycling stability of 188 cycles at 500 mA g−1 are achieved. The corresponding catalytic mechanism of Bi 2 Te 3 mainly originates from its stack surface derived homogenous electronic state and high conductivity. [Display omitted] • Bi 2 Te 3 with exposed 2D surface plane exhibits excellent catalytic activity in LOBs. • The superior catalytic capability of Bi 2 Te 3 originates from 2D surface (001) plane. • Side edge planes of 2D materials contribute to the formation of side products. [ABSTRACT FROM AUTHOR]