Formation of Triple-Shelled Molybdenum-Polydopamine Hollow Spheres and Their Conversion into MoO2/Carbon Composite Hollow Spheres for Lithium-Ion Batteries

Unique triple-shelled Mo-polydopamine (Mo-PDA) hollow spheres are synthesized through a facile solvothermal process. A sequential self-templating mechanism for the multi-shell formation is proposed, and the number of shells can be adjusted by tuning the size of the Mo-glycerate templates. These triple-shelled Mo-PDA hollow spheres can be converted to triple-shelled MoO2/carbon composite hollow spheres by thermal treatment. Owing to the unique multi-shells and hollow interior, the as-prepared MoO2/carbon composite hollow spheres exhibit appealing performance as an anode material for lithium-ion batteries, delivering a high capacity of ca. 580 mAh g(-1) at 0.5 A g(-1) with good rate capability and long cycle life.