In situ synthesis of polydopamine–Ag hollow microspheres for hydrogen peroxide sensing

In this paper, monodisperse polydopamine (PDA)–Ag hybrid hollow microspheres were synthesized by self-polymerization of dopamine on ZnO microspheres as sacrificial templates. The templates were dissolved in basic media and in situ reduced the incorporated Ag+ ion with ascorbic acid. The as-prepared PDA–Ag composites modified glassy carbon electrode exhibited a broad linear range of 0.092–20 mM for H2O2 determination, with a remarkable sensitivity of 6.79 μA mM−1, a detection limit of 1.97 μM (S/N = 3), and rapid response (within 5 s). Moreover, the electrode showed good reproducibility, anti-interferant ability and long-term stability.

. In this work, well-defined polydopamine (PDA)–Ag hollow microspheres were synthesized by self-polymerization of dopamine and using ZnO microspheres as sacrificial templates in basic media. Meanwhile, the Ag+ ion grafted onto the PDA shells, was in situ reduced by ascorbic acid and formed Ag nanoparticles. The resulting products exhibited enhanced electrocatalytic ability towards the reduction of H2O2.Figure optionsDownload as PowerPoint slideHighlights
► Well-defined ZnO microspheres were prepared in large scale by a novel hydrothermal method.
► The ZnO microspheres were used as sacrificial templates for polydopamine (PDA)–Ag hollow microspheres in basic media.
► Ag nanoparticles were obtained via in situ reduction of the incorporated Ag+ ion on PDA surface by ascorbic acid.
► The PDA–Ag hollow microspheres showed high electrocatalytic ability towards H2O2.