Pt/Ti3C2 electrode material used for H2S sensor with low detection limit and high stability

Traditional Pt/C electrode materials are prone to corrosion and detachment during H₂S detection, leading to a decrease in fuel cell-type sensor performance. Here, a high-performance H₂S sensor based on Pt loaded Ti₃C₂ electrode material with -O/-OH terminal groups was designed and prepared. Experimental tests showed that the Pt/Ti₃C₂ sensor has good sensitivity (0.162 μA/ppm) and a very low detection limit to H₂S (10 ppb). After 90 days of stability testing, the response of the Pt/Ti₃C₂ sensor shows a smaller decrease of 2% compared to that of the Pt/C sensor (22.9%). Meanwhile, the sensor also has high selectivity and repeatability. The density functional theory (DFT) calculation combined with the experiment results revealed that the improved H₂S sensing mechanism is attributed to the fact that the strong interaction between Pt and Ti₃C₂ via the Pt-O-Ti bonding can reduce the formation energy of Pt and Ti₃C₂, ultimately prolonging the sensor's service life. Furthermore, the catalytic property of Pt can decrease the adsorption energy and dissociation barrier of H₂S on Pt/Ti₃C₂ surface, greatly enhance the ability to generate protons and effectively transfer charges, realizing good sensitivity and high selectivity of the sensor. The sensor works at room temperature, making it very promising in the field of H₂S detection in future.