Synthesis of Ni-doped α-MoO3 nanolamella and their improved gas sensing properties

•Ni-doped α-MoO3 nanolamella with different Ni concentrations was synthesized.•Influence on formaldehyde sensing properties caused by Ni doping was studied.•Ni-doped α-MoO3 highly improved formaldehyde sensing properties.

In this work, α-MoO3 and Ni-doped α-MoO3 were synthesized through a facile solvothermal method and various techniques were employed to study the phase and morphological properties. The gas sensing measurements showed that 5 mol% Ni-doped α-MoO3 had superior formaldehyde sensing capability compared with pure α-MoO3. The maximum response value approached 41-100 ppm formaldehyde at 255 °C, which was about 4.1 times bigger than that of pure α-MoO3. In addition, the 5 mol% Ni-doped α-MoO3 gas sensor was also found to have lower detection limit and better selectivity to formaldehyde. The mechanism involved in gas sensing performance of Ni-doped α-MoO3 was also discussed.