HIERARCHICAL POLYTHIOPHENE-COATED MnO₂ NANOSHEETS AS NON-PRECIOUS ELECTRO-CATALYST TO OXYGEN REDUCTION

In this work, hierarchical polythiophene-coated MnO ₂ nanosheets have been synthesized employing a modified interfacial process. The materials have been thoroughly characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy and electron microscopy. It is found that the in situ generated polythiophene-coating cannot only retard the overgrowth of nuclei but also stabilize the ultrathin nanosheets (less than 5 nm), and enhance the electronic conductivity of MnO ₂ as well. The cyclic voltammetric measurement verifies that the prepared nanocomposite electrode possesses good electro-catalytic activity to oxygen reduction reaction (ORR) in alkaline media. The corresponding electro-catalytic mechanism on ORR is also investigated. The excellent activity of the synthesized nanocomposite brings about an overall 4-electron reduction of oxygen.