Nitroxide polymer brushes grafted onto silica nanoparticles as cathodes for organic radical batteries

► Nitroxide polymer brushes on silica nanoparticles as cathodes were prepared by ATRP. ► The nitroxide polymer brush prevents the polymer from dissolving into electrolytes. ► The nitroxide polymer brushes serve as bind-free cathode materials. ► The nitroxide polymer brushes demonstrate excellent electrochemical performances.