Ultrafast Carbonized Wood of Electrode-Scaled Aligned-Porous Structure for High-Performance Lithium Batteries

The use of carbonized wood in various functional devices is attracting considerable attention due to its low cost, vertical channels, and high electrical conduction. However, the conventional carbonization method requires a long processing time and an inert atmosphere. Here, a microwave-assisted ultrafast carbonization technique was developed that carbonizes natural wood in seconds without the need for an inert atmosphere, and the obtained aligned-porous carbonized wood provided an excellent electrochemical performance as an anode material for lithium-ion batteries. This ultrafast carbonization technique simultaneously produced ZnO nanoparticles during the carbonization process that were uniformly distributed on the aligned-porous carbon. The hierarchical structure of carbonized wood functionalized with ZnO nanoparticles was used as a host for achieving high-performance lithium–sulfur batteries: the highly conductive carbonized wood framework with vertical channels provided good electron transport pathways, and the homogeneously dispersed ZnO nanoparticles effectively adsorbed lithium polysulfide and catalyzed its conversion reactions. In summary, a new method was developed to realize the ultrafast carbonization of biomass materials with decorated metal oxide nanoparticles.