One-step synthesis of Ni(OH)2/MWCNT nanocomposites for constructing a nonenzymatic hydroquinone/O2 fuel cell

Abstract

In this work, a H-type hydroquinone/O₂ fuel cell was assembled and shows high energy density in neutral phosphate buffer solution at moderate temperature. The anodic material, Ni(OH)₂/MWCNTs, was synthesized by a one-step hydrothermal synthesis method to oxidize hydroquinone. The cathode material, Pt/MWCNTs, was obtained by an electrodeposition method, and shows great oxygen reduction reaction (ORR) activity. The properties and the morphology of Ni(OH)₂/MWCNT nanocomposites were characterized by TEM, XPS, EDS-mapping and electrochemical methods, like cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results show that Ni(OH)₂/MWCNTs can effectively oxidize hydroquinone and play a dominant role in enhancing the fuel cell performance. The nonenzymatic fuel cell possesses a high power density of 0.24 mW cm⁻² at a cell potential of 0.49 V.