Mo₂C is a two-dimensional material with high electrical conductivity, low power consumption, and catalytic effect, which has promising applications in the field of microfluidic gas detection. First principles were used to study the adsorption characteristics of Mo₂C monolayer on four typical decomposition gases of SF₆ (H₂S, SO₂, SOF₂, and SO₂F₂), and to explore the feasibility of its application in the detection of SF₆ decomposition components. The results showed that Mo₂C chemisorbed all four gases, and the adsorption capacity was H₂S < SO₂ < SOF₂ < SO₂F₂. The adsorption mechanism of Mo₂C as a microfluidic sensor was analyzed in combination with its charge-density difference and density of states. On the other hand, the different work-function change trends after adsorbing gases provide the possibility for Mo₂C to selectively detect gases as a low-power field-effect transistor sensor. All content can be used as theoretical guidance in the realization of Mo₂C as a gas-sensitive material for the detection of SF₆ decomposition components.

Based on the wide application of sulfur hexafluoride (SF₆) gas in the power industry, the analysis and detection of its decomposition components have become important technical means for state detection and fault evaluation of gas-insulated equipment. The gas-sensitive characteristics and adsorption mechanism of the SnS₂ sensor for SO₂ and SOF₂ gases were investigated using SO₂ and SOF₂, the main SF₆ decomposition components, as the target detection gases. SnS₂ gas-sensitive materials and components were prepared, and the temperature response, concentration response, response recovery and stability of the SnS₂ sensor for the two SF₆ decomposition components were tested based on the gas-sensitive test platform. The results demonstrate that the sensor had the best working performance at 200 °C, with obvious response and ideal recovery for both target gases and good stability in a certain time. Based on the first principle, the SnS₂ surface structure model and the target gas adsorption model were established, and the adsorption mechanism was analyzed in terms of frontier molecular orbital theory to verify the correctness of the gas-sensitive test results. The gas-sensitive test analysis and simulation calculation can provide data basis and theoretical support for the study of SF₆ decomposition components detected by gas sensors.

The detection of SF₆ decomposition components using gas-sensitive sensors is significantly important for characterizing internal insulation failures and assessing the operational status of SF₆ gas-insulated equipment. In this paper, the adsorption properties of GeP₃ monolayers for SO₂, H₂S, SOF₂ and SO₂F₂ gases were investigated based on density functional theory. Four gas adsorption systems were constructed, and the adsorption mechanisms and sensing characteristics of GeP₃ monolayers on target gases were investigated by calculating parameters such as adsorption energy, charge transfer, density of states, and recovery time, along with their potential application as resistive gas sensors and field-effect transistor sensors. It is demonstrated that GeP₃ monolayers were suitable for the detection of SO₂, H₂S, SOF₂ and SO₂F₂ gases, all of which exhibited good chemisorption with adsorption energies of −1.36 eV, −0.78 eV, −1.82 eV and −2.91 eV, respectively. The adsorption of SO₂ and H₂S is found to cause a significant change in the conductivity of the GeP₃ monolayers, and desorption is achieved at the optimal operating temperature in only 54.428 s and 10.686 s, respectively. Also the adsorption of SOF₂ and SO₂F₂ can make the work function of the GeP₃ monolayers significantly larger. Consequently, the GeP₃ monolayers have the potential to be used as a resistive gas sensor for SO₂ and H₂S gases, or as a field effect transistor sensor for SOF₂ and SO₂F₂ gases. This study provides theoretical guidance for the development of GeP₃-based sensors for monitoring the insulation status and operational conditions of SF₆ gas-insulated equipment.