p-p heterojunction composite of NiFe2O4 nanoparticles-decorated NiO nanosheets for acetone gas detection

A series of NiFe2O4/NiO composites composed of NiFe2O4 nanoparticles dispersing on NiO nanosheets were successfully prepared under solvothermal condition using NiO precursor and FeCl3 center dot 6H(2)O. Gassensing performance assessment demonstrated the formation of composites can improve the properties effectively. The sensor based on sample Fe/Ni-24.9 at% exhibited the optimal gas-sensing performance, showing fast response/recovery, good repeatability and high response of similar to 23.0 to 50 ppm acetone at 280 degrees C, which was about 1.8 times and 2.2 times of the pristine NiO and NiFe2O4. The excellent sensing performance can be ascribed to the p-p heterojunction between the NiO and NiFe2O4, which may decrease the charge carrier concentration in NiO near the heterojunction and bring about larger resistance variation upon the adsorption of target gas. (C) 2020 Elsevier B.V. All rights reserved.