Synthesis of multifarious hierarchical flower-like NiO and their gas-sensing properties

•Three different kinds of flower-like NiO nanostructure were synthesized.•Effects of PVP, reaction time and temperature were investigated in detail.•Growth mechanism of the camellia-like NiO was discussed.•Sensor with camellia-like NiO showed the good performance toward the alcohol.

We successfully synthesized variant hierarchical assembled flower-like NiO with the reaction of nickel chloride and aqueous ammonia via a simple hydrothermal technique and subsequent calcination. Polyvinyl Pyrrolidone (PVP), Cetyl Trimethyl Ammonium Bromide (CTAB) and glycerol were chosen to play important roles in synthesis of disparate 3D NiO nanostructures. Through our repeated explorations, the influences of PVP, reaction time and temperature on the formation of camellia-like NiO were investigated in detail. The gas-sensing performances of the as-prepared NiO were investigated towards ethanol. It is noted that the camellia-like NiO sensor displayed particular response to the target gas rendering NiO as a potential gas-sensing material for a broad range of future sensor applications.

Graphical abstractWe successfully synthesized three kinds of hierarchical assembled flower-like NiO with the reaction of nickel chloride and aqueous ammonia via a simple hydrothermal technique and subsequent calcination.Figure optionsDownload full-size imageDownload as PowerPoint slide