ZnO nanoparticles encapsulated in three dimensional ordered macro-/mesoporous carbon as high-performance anode for lithium-ion battery

Abstract

Herein, we report a three-dimensionally (3D) ordered macro-/mesoporous carbon (3DOM-mC) as the ZnO nanoparticles support for the anode material in lithium-ion batteries (LIBs). The 3DOM-mC is synthesized by the typical dual-templating method that combines the hard-templating (silica opal as template) and soft-templating techniques using resol (phenol/formaldehyde) as the carbon source. The prepared 3DOM-mC material having ordered interconnected macropores and mesopores is then applied to support ZnO nanoparticles to form the ZnO/3DOM-mC composite via a simple in situ solution growth approach. In the ZnO/3DOM-mC composite, the ZnO nanoparticles (∼4.5 nm) are evenly dispersed on the macropore walls of the 3DOM-mC. The ZnO/3DOM-mC composite (40 wt% ZnO loading) anode shows an enhanced LIB performance delivering a specific capacity of 973.3 mAh g−1 after 100 cycles and 1396.6 mAh g−1 after 300 cycles at 0.1 C. This good electrochemical performance of the ZnO/3DOM-mC is ascribed to the ordered interconnected macropores of the 3DOM-mC that can provide the rapid diffusion of Li ions and electrolytes and the ordered mesopores that can buffer the volume expansion of ZnO during the cycling operation.