Effect of Pr/Zn on the anti-humidity and acetone-sensing properties of CoO prepared by electrospray

Co 3 O 4 is a P-type metal-oxide semiconductor which can realize acetone detection at a lower temperature, but the lower working temperature brings the enhanced humidity effect. In order to solve the problem of a Co 3 O 4 gas sensor being easily affected by humidity, an acetone-sensing material of Co 3 O 4 mixed with Pr/Zn was prepared by electrospray in this work. The optimal working temperature of Pr/ZnCo 3 O 4 is 160 C, and the detection limit can reach 1 ppm. The fluctuation of the acetone response is about 7.7% in the relative humidity range of 3090%. Compared with pure Co 3 O 4 , the anti-humidity property of this material is obviously enhanced, but the gas-sensing response deteriorates. Compared with PrCo 3 O 4 , the anti-humidity and acetone sensing properties of Pr/ZnCo 3 O 4 were both improved. The morphology, composition, crystal state and energy state of the material were analyzed by SEM, EDS, XRD and XPS. The material of Pr/ZnCo 3 O 4 is a multi-component mixed material composed of PrCoO 3 , ZnO, Pr 6 O 11 and Co 3 O 4 . The improved anti-humidity and acetone sensing properties exhibited by this material are the result of the synergistic effect of ZnO and Pr 3+ . With the synergistic effect of Pr and Zn, the material of Co 3 O 4 mixed with Pr/Zn exhibits improved properties of anti-humidity and acetone sensitivity.