Local atomic structure order and electrochemical properties of NiO based nano-catalysts for ethanol sensing at room temperature

The increased emission of volatile organic compounds (VOCs) and their adverse effects on environment led to the development of more economical and sustainable sensing technologies. Ethanol is a member of VOC family and has harmful effect on human health and environment. Therefore, an efficient electrocatalyst for ethanol detection at ambient temperature is highly desirable. Here we present the successful synthesis of NiO based sensing material where modification of NiO was carried out by transition metals doping (8% Cu and 8% Zn) and codoping (4% Cu + 4% Zn). The synthesized catalysts were characterized by several techniques like powder X ray diffraction, Raman spectroscopy, scanning electron microscopy, X-ray absorption fine structure, Brunauer–Emmett–Teller and diffuse reflectance spectroscopy. The electrochemical responses showed that the codoped NiO has a better catalytic performance towards ethanol detection with a wide linear range from 3 mM to 12 mM, and a low detection limit (LOD) of 2.2 mM. The striking analytical performance and facile preparation technique make this catalyst effective for efficient enzyme-free electrochemical ethanol sensing.