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Real-time monitoring of SF6 status is of exceptional importance to ensure stable operation of the power system, to promptly diagnose whether an insulation failure has occurred and to assess the severity. Considering the excellent physicochemical properties and insulation defects of hexagonal boron nitride, the strategy of surface modification, namely, hydrogenation, fluorination, and combinations of the two ways, is proposed to improve its chemical activity, and the gas-sensing potential of the most effective one is investigated using density functional theory. The typical adsorption models of SF6 decomposition component gases on the surface of F-BN-H are constructed, and the most stable adsorption structures with their density of states, molecular orbitals, and sensing responses are analyzed. The results show that F-BN-H has good sensitivity to decomposition components of SF6. To be specific, SO2 and SOF2 have good adsorption properties, prominent charge transfer, and distinct change in electronic properties. The response of gas adsorption can be detected timely by the change in conductivity, and, additionally, the adsorbent has fast desorption capacity at room temperature. These results indicate that the F-BN-H-based gas sensor is a qualified potential candidate with dependable application and recoverability for detecting SF6 decomposition in high-voltage insulated equipment. [ABSTRACT FROM AUTHOR]

Laser engraving is carried out on the both sides of PI film to achieve constant temperature gas monitor and early automatic self-alarm. [Display omitted] • The LIG IDEs serve gas sensor, and rectangular LIG is usable in dual-working mode. • The rectangular LIG provides a constant working temperature under a DC voltage. • The NO 2 monitor with heating condition overcomes the inability to desorb at RT. • Let the device emit an acoustic alarm once NO 2 concentration is beyond threshold. The increasingly serious air pollution problem makes the development of high-performance gas monitoring system extremely urgent. Especially for nitrogen dioxide (NO 2), which is harmful to both people and the environment. The combination of reliable real-time monitoring and early warning is of great significance yet less study. Here, we designed a laser-induced graphene (LIG)-based multi-functional NO 2 monitor and self-alarm (MMSA), in which a rectangle area is used as a dual-functional module to realize high-performance temperature condition and acoustic alarm by applying direct/alternating current voltage excitation source. The molybdenum disulfide (MoS 2) sensitive material works in concert with the LIG interdigital electrodes (IDEs), and the gas monitor achieves high sensitivity (86.81% for 5 ppm, and 22.90% for 250 ppb) and excellent recoverability, aided by the good electrothermal property of LIG, overcoming the dilemma of poor sensing performance of MoS 2 at room temperature (RT). To top it off, the thermoacoustic effect of the LIG could bring about an intuitional sound signal, and a proof-of-concept demonstrates the timely acoustic warning response of the MMSA to exceeded NO 2 concentrations. [ABSTRACT FROM AUTHOR]