Modified Nickel Nanowires for Electro-Catalytic Oxidation of Formaldehyde in Alkaline Solutions

Abstract

A Ni nanowires-based electrodes for formaldehyde (HCHO) detection were fabricated via a template-assisted electrodeposition. The as-deposited Ni nanowires (NWs) were characterized by scanning electron microscope (SEM). In order to form an active redox couple of Ni(OH)2/NiOOH on the surface of nanowires, the Ni NWs were electrochemically modified in 0.5 mol L−1 KOH using cyclic voltammetry. The presence of Ni(OH)2/NiOOH on the surface of Ni NWs was confirmed by transmission electron microscopy (TEM). Furthermore, the ability of modified Ni NWs-based electrode (i.e., receptor element) was investigated for HCHO electro-oxidation in alkaline media via cyclic voltammetry and amperometry. The fabricated Ni NWs-based electrode exhibited fast response (3s), good selectivity, a high sensitivity and low limit of detection 0.8 μmol L−1.

Keywords

• formaldehyde
• Ni nanowires electrode
• electro-oxidation
• electro-catalysis