Surface-Modified In₂O₃ for High-Throughput Screening of Volatile Gas Sensors in Diesel and Gasoline

In this paper, with the help of the method of composite materials science, parallel synthesis and high-throughput screening were used to prepare gas sensors with different molar ratios of rare earths and precious metals modified In₂O₃, which could be used to monitor and warn the early leakage of gasoline and diesel. Through high-throughput screening, it is found that the effect of rare earth metal modification on gas sensitivity improvement is better than other metals, especially 0.5 mol% Gd modified In₂O₃ (Gd_0.5In) gas sensor has a high response to 100 ppm gasoline (R/R = 6.1) and diesel (R/R = 5) volatiles at 250 °C. Compared with the existing literature, the sensor has low detection concentration and suitable stability. This is mainly due to the alteration of surface chemisorption oxygen caused by the catalysis and modification of rare earth itself.