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[Display omitted] • ZnMn 2 O 4 nanomaterial was firstly used in cataluminescence sensor. • The novel sensor exhibited excellent selectivity and high sensitivity toward H 2 S. • The cataluminescence sensing mechanism of H 2 S on ZnMn 2 O 4 -0.3 was further explored using density functional theory. Regarded as a highly toxic pollutants, H 2 S can severely threaten human health. Therefore, it is critical to develop an efficient sensing material to detect H 2 S gas. In this study, three nanomaterials—ZnMn 2 O 4 , ZnMn 2 O 4 -0.3, and ZnMn 2 O 4 -0.6—were successfully prepared via a simple hydrothermal method that is modified by the use of carbon spheres, and then applied to the field of cataluminescence (CTL). The nanostructure, surface composition, and morphology of the prepared catalysts were characterized via X-ray diffraction analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. Among the nanomaterials, ZnMn 2 O 4 -0.3 exhibited the highest CTL properties, including excellent H 2 S selectivity, because of its high content of surface-adsorbed O 2. Under optimized detection conditions, a good linear relationship (r = 0.997) of CTL intensity versus H 2 S concentration was obtained in the linear range of 0.810 – 26.3 μg mL−1, and the detection limit (S/N = 3, DL) was 0.405 μg mL−1. In addition, the CTL sensing mechanism for H 2 S on the ZnMn 2 O 4 -0.3 material was explored using the density functional theory. In comparison with previously reported various sensors based on CTL for H 2 S determination, ZnMn 2 O 4 -0.3 exhibited properties similar to or higher than other materials because of its low working temperature, fast response, and low DL, thereby confirming that ZnMn 2 O 4 can be used as a material for CTL detection of H 2 S. [ABSTRACT FROM AUTHOR]

Vacancy regulation is considered to be an effective means to improve the properties of materials, which has been applied in the fields of catalysis, electricity and optics. Herein, different contents of nitrogen vacancy in graphitic carbon nitride (g-C 3 N 4) could be modulated via changing temperature of secondary calcination. Results showed the introduction of nitrogen vacancy significantly promoted the cataluminescence (CTL) intensity towards ammonium sulfide ((NH 4) 2 S) and the CTL performance increased regularly with the increaseing vacancy content. The positive effect of nitrogen vacancy on CTL intensity of (NH 4) 2 S was unveiled in-depth by the experiment and density functional theory (DFT). Moreover, a cutting-edge CN-600-based sensor was established for the highly sensitive detection of (NH 4) 2 S. The sensor possessed excellent selectivity and stability, and a low detection limit (0.16 μg mL−1). Noteworthily, this study presents novel mentality for designing materials with improved catalytic activity. [Display omitted] • The nitrogen vacancy content in g-C 3 N 4 was successfully modulated by adjusting temperature of secondary calcination. • The mechanism of enhanced CTL performance of (NH 4) 2 S on g-C 3 N 4 surface modulated by nitrogen vacancy was revealed. • The constructed CN-600-based sensor exhibited excellent selectivity and stability for (NH 4) 2 S sensing. [ABSTRACT FROM AUTHOR]