Biomass based composite used as anode materials: Porous ZnO anchored on the rice husk-derived carbon substrate for Li-ion batteries

Abstract

As an anode material, ZnO has attracted the interest of researchers because of its high theoretical specific capacity. Unfortunately, low conductivity and pulverization caused by the volume change of ZnO have been two stumbling blocks on its application. Herein, we designed a novel structure that porous ZnO crystals are firmly anchored on the surface of hollow carbon spheres derived from rice husk (RH). When used as an anode material for lithium-ion batteries, the composite material delivered a high discharge specific capacity of 1111 mAh g−1 at 0.2C after 150 cycles. The excellent electrochemistry performance is attributed to good strain accommodation of carbon skeleton and its nanoporous structure. The unique skeleton of the three-dimensional hollow carbon nanospheres enhanced conductivity and alleviated the volume expansion of ZnO nanoparticles during charge and discharge. Additionally, the pore-rich structure promoted the intercalation/deintercalation of lithium ions and the charge transfer on the electrode.