Poly(methylene blue) doped silica nanocomposites with crosslinked cage structure: Electropolymerization, characterization and catalytic activity for reduction of dissolved oxygen

► PMB polymer exhibited electrocatalytic activity for reduction of dissolved oxygen. ► PMB@SiO2 nanocomposites were electrochemically polymerized on GCE surface. ► The nanocomposites provided an improved electrocatalytic activity for DO reduction. ► The nanocomposites showed an excellent ability to resist interference.