Integrated sensing array of the perovskite-type LnFeO3 (LnLa, Pr, Nd, Sm) to discriminate detection of volatile sulfur compounds

Highlights: • The LnFeO₃ (LnLa, Pr, Nd, Sm) nanoparticles are prepared by the citrate sol-gel method. • Clearly distinct signatures are seen associated with four typical VSCs (H₂S, CS₂, DMS, DMDS) the LnFeO₃ sensor array. • Pattern recognition of four typical VSCs with different concentrations can be achieved through PCA. • The sensors exhibited superior response, selectivity and long-term stability in VSCs detection at 210 °C. Distinguishing toxic gases among the various volatile sulfur compounds (VSCs) is of significant practical value for atmospheric and environmental pollution monitoring, industrial monitoring, and even for medical diagnostics (where VSCs are indicators of diseases). The particular challenge lies in the detection and discrimination of sulfur-containing gases such as dimethyl disulfide (DMDS), methyl sulfide (DMS), hydrogen sulfide (H₂S), and carbon disulfide (CS₂) is of value. Herein, single-phase perovskite-type LnFeO₃ nanoparticles were prepared by the citrate sol-gel method. Their gas sensing characteristics regard to the four typical VSCs were investigated. We found that the gas response of the p-type semiconductor LnFeO₃ gas sensors to the four typical VSCs are significantly different. In addition, the sensors offer high performance, good tolerance to environmental changes and long-term stability for detecting VSCs gas at an operating temperature of 210 °C. A new design of sensor array was realized by integrating a series of LnFeO₃ materials, which revealed excellent recognition ability for various VSCs, showing promise for real time monitoring.