On the basis of cataluminescence (CTL) emission on the surface of CoFe₂O₄ nanomaterial, a novel and sensitive sensor for the determination of ammonium sulfide was developed. The CTL characteristics and the optimal conditions including three nanomaterials morphology, air flow rate, working temperature and wavelength were investigated. Under the optimized conditions, the linear range of CTL intensity versus concentration of ammonium sulfide was 0.13～13 mg/L (r＝0.9951, n＝9) with a detection limit of 0.04 mg/L (3σ). The relative standard deviation (RSD) for 1.3 mg/L ammonium sulfide was 1.8% (n＝8). Interference experiments showed that there was no response from common foreign substances, and the present sensor can be used for the continuous determination of 1.3 mg/L ammonium sulfide more than 60 h over two weeks with a RSD of less than 5%. Meanwhile, this sensor was successfully applied to determine ammonium sulfide in artificial samples with recoveries from 94.7% to 103.9%.

Key words: cobalt iron oxide, cataluminescence, ammonium sulfide, gas sensor