Detection of acetylacetone using p-type AgCuO2 nanoparticles at a low operation temperature

Metal oxide semiconductors with the chemiresistive effect were critical in gas sensing applications, particularly in the trace detection of volatile organic compounds . In this work, we presented p-type AgCuO 2 nanoparticles based gas sensor, which exhibited a high susceptibility to acetylacetone (77.9–25 ppm) at a low operation temperature of 130 °C with short response/recovery time (86 s/130 s) and a low detection limitation down to sub-ppm level (58 ppb), outperforming the congeneric AgCrO 2 , CuCrO 2 , Ag 2 O, CuO, and commercial SnO 2 gas sensors. Based on the microstructural characterization and gas test results, the gas sensing mechanism was revealed by the first-principles calculations on the basis of density function theory. The chemiresistive signal was believed to stem from the direct adsorption followed by the charge transfer, reflected by the counterpart of the calculated adsorption energy with the Bader charge and the response order to the test gases. This study provided a new route to design of the sensitive oxide material for the advanced gas sensing towards the specific target gas. • Gas sensing mechanism of AgCuO 2 is studied experimentally and theoretically. • The importance of the advantageous valence and oxygen species to charge transfer is highlighted. • The AgCuO 2 based gas sensor exhibits ultralow detection limit to acetylacetone down to 100 ppb. • The gas sensor performs superior performances at a lower working temperature.