C3ta01272g 5709..5714

Significant efforts have been devoted to synthesis and characterization of engineered silicon nanostructures able to withstand the large stresses and strains produced by lithium alloying/dealloying reactions during electrochemical cycling. Less attention has been given to ensuring robust connection between silicon and its host structure in the anode. The current work develops a new methodology to create nanocomposites in which silicon nanoparticles are uniformly dispersed in a mesoporous carbon host. The composite is synthesized through copolymerization of acrylonitrile and silicon nanoparticles densely functionalized with vinyl groups, which serve as seeds for free radical dispersion polymerization, followed by carbonization of the PAN coating/network. The method yields nanocomposites with high, reversible capacities and stable cycling performance.