Facile preparation of monolayer NiO thin film for high performance THF sensor

ABSTRACTHigh quality monolayer NiO thin film was fabricated by an oil–water interface self-assembly strategy. Polystyrene spheres were used as templates. The as-prepared film composed by a series of ordered hexagonal close-packed bowl-like array with an average diameter of about 700 nm. The monolayer NiO thin film deposited on aluminium oxide substrate with Au interdigital electrode on the surface can be directly used as a tetrahydrofuran (THF) gas sensor. The NiO thin film gas sensor presents great selectivity, fast response, and recovery time. The response of the monolayer NiO thin film sensor was about 15.14–100 ppm THF at a working temperature of 325 °C. The excellent performance can be attributed to the bowl-like structure and good contact with the Au coated aluminium oxide substrate.