Firstly, the void space provided by porous structure can mitigate the volume change effect during the repeated charge discharge cycling process, leading to enhanced capacity retention.
The composites could effectively improve the kinetics of electronic transportation and mitigate the volume expansion of electrodes during discharge/charge process.
This is because the interior hollow structure can provide sufficient space to mitigate the volume change and pulverization, which is caused by the Li+ insertion/extraction [42, 43, 44, 45].
The porous nanotubular structure is expected to mitigate the volume expansion of SnO2, while the as-formed Cu from CuO upon lithiation allows faster electron transport by improving the low conductivity of SnO2.
The improved electrochemical performance is mainly attributed to the mesoporous structure and the coating layer of PPy, which effectively mitigate the volume change and enable good conductivity and thus enhance fast charge transfer.
This 3D ordered hollow structure not only offers good electronic transportation routes and ionic conductive channels, but also effectively relieves the stress and mitigates the volume variation during lithiation/delithiation process as reflected by the high cycle stability and excellent rate capability as anode materials for lithium ion batteries.
Based on electrochemical analyses, we determined that Sb acts as an active material, and both Al and carbon create a hybrid buffering matrix that mitigates the volume expansion of the active material during lithiation/delithiation to a greater degree than that by a pure metallic matrix (AlSb).
Furthermore, the hollow space within the SnO2 nanoparticles effectively mitigates the enormous volume change during charge discharge cycling.
The RGO not only serves as a soft and robust matrix to mitigate the large volume change during cycling but also acts as the electron highway.
